Multifocal contact lens displaying improved vision attributes

ABSTRACT

Described are multifocal contact lenses that contain high energy visible (HEV) light absorbing compounds and their use for improving one or more vision attributes.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application Ser. No. 62/894,015, filed Aug. 30, 2019, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The invention relates to multifocal contact lenses that contain high energy visible (HEV) light absorbing compounds and their use for improving one or more vision attributes.

BACKGROUND OF THE INVENTION

As individuals age, their eyes are less able to accommodate, or bend their natural or crystalline lens, to focus on objects that are relatively near to the observer. This condition is known as presbyopia. More specifically, when an individual is born, the crystalline lens is pliable which makes it capable of a high degree of accommodation. As the individual ages, the crystalline lens gradually becomes more rigid and thus less able to accommodate. Similarly, for persons who have had their natural or crystalline lens removed and an intraocular lens or IOL inserted as a replacement, the ability to accommodate is absent.

Various classes of multifocal contact lens designs have been offered for the treatment of presbyopia. These include bifocal contact lenses, trifocal contact lenses, and lenses containing concentric rings, aspheric designs, as well as diffractive designs. For instance, a multifocal contact lens, with or without astigmatic correction, may contain a region in which the power continuously increases from distance to near optical power or continuously decreases from near to distance optical power from the lens center and radially toward the edge of the optical zone.

Although multifocal lenses are effective at improving vision in presbyopic patients, many shortcomings still exist. For example, many presbyopic patients remain unsatisfied with their multifocal contact lenses, for instance because of issues with vision clarity and quality, glare, and the like. It would therefore be an advantage in the art to develop new technologies that further improve a presbyopic patient's experience with multifocal contact lenses.

SUMMARY OF THE INVENTION

The invention relates to multifocal contact lenses. The contact lenses filter high energy visible (HEV) light, and optionally UV light, while substantially transmitting (e.g., greater than 80% transmission) at wavelengths longer than about 450 nm. It has been discovered that such lenses provide improvement in a number of vision attributes, including improvements in one or more of quality of vision at different vergences, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast, when compared to multifocal contact lenses that do not filter HEV light.

Accordingly, in one aspect, the invention provides a contact lens. The contact lens is a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible (HEV) light absorbing compound (which may be a polymerizable HEV light absorbing compound), wherein the contact lens is a multifocal contact lens. The contact lens may transmit from 0 percent to 70 percent, or from 1 percent to 70 percent, of light across a wavelength range of 400 to 409 nm.

In another aspect, the invention provides a method for improving a vision attribute in a presbyopic contact lens wearer. The method comprises: providing the presbyopic contact lens wearer with a multifocal contact lens that is a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a vision attribute improving amount of a high energy visible (HEV) light absorbing compound, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.

In a further aspect, the invention provides the use of a multifocal contact lens for improving at least one vision attribute selected from quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast, the multifocal contact lens being a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and an attribute improving amount of a high energy visible light absorbing compound.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows UV-VIS transmission spectrum of silicone hydrogel contact lenses containing a HEV light absorbing compound as described in Example 5.

FIG. 2 shows the results of clinical testing conducted according to Example 6.

DETAILED DESCRIPTION OF THE INVENTION

It is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or being carried out in various ways using the teachings herein.

With respect to the terms used in this disclosure, the following definitions are provided.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. The polymer definitions are consistent with those disclosed in the Compendium of Polymer Terminology and Nomenclature, IUPAC Recommendations 2008, edited by: Richard G. Jones, Jaroslav Kahovec, Robert Stepto, Edward S. Wilks, Michael Hess, Tatsuki Kitayama, and W. Val Metanomski. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

As used herein, the term “(meth)” designates optional methyl substitution. Thus, a term such as “(meth)acrylates” denotes both methacrylates and acrylates.

Wherever chemical structures are given, it should be appreciated that alternatives disclosed for the substituents on the structure may be combined in any combination. Thus, if a structure contained substituents R* and R**, each of which contained three lists of potential groups, 9 combinations are disclosed. The same applies for combinations of properties.

When a subscript, such as “n” in the generic formula [***]_(n), is used to depict the number of repeating units in a polymer's chemical formula, the formula should be interpreted to represent the number average molecular weight of the macromolecule.

The term “individual” includes humans and vertebrates.

The term “contact lens” refers to an ophthalmic device that can be placed on the cornea of an individual's eye. The contact lens may provide corrective, cosmetic, or therapeutic benefit, including wound healing, the delivery of drugs or nutraceuticals, diagnostic evaluation or monitoring, ultraviolet light absorbing, visible light or glare reduction, or any combination thereof. A contact lens can be of any appropriate material known in the art and can be a soft lens, a hard lens, or a hybrid lens containing at least two distinct portions with different physical, mechanical, or optical properties, such as modulus, water content, light transmission, or combinations thereof.

The lenses of the present invention may be comprised of silicone hydrogels or conventional hydrogels. Silicone hydrogels typically contain at least one hydrophilic monomer and at least one silicone-containing component that are covalently bound to one another in the cured device.

“Target macromolecule” means the macromolecule being synthesized from the reactive monomer mixture comprising monomers, macromers, prepolymers, cross-linkers, initiators, additives, diluents, and the like.

The term “polymerizable compound” means a compound containing one or more polymerizable groups. The term encompasses, for instance, monomers, macromers, oligomers, prepolymers, cross-linkers, and the like.

“Polymerizable groups” are groups that can undergo chain growth polymerization, such as free radical and/or cationic polymerization, for example a carbon-carbon double bond which can polymerize when subjected to radical polymerization initiation conditions. Non-limiting examples of free radical polymerizable groups include (meth)acrylates, styrenes, vinyl ethers, (meth)acrylamides, N-vinyllactams, N-vinylamides, O-vinylcarbamates, O-vinylcarbonates, and other vinyl groups. Preferably, the free radical polymerizable groups comprise (meth)acrylate, (meth)acrylamide, N-vinyl lactam, N-vinylamide, and styryl functional groups, and mixtures of any of the foregoing. More preferably, the free radical polymerizable groups comprise (meth)acrylates, (meth)acrylamides, and mixtures thereof. The polymerizable group may be unsubstituted or substituted. For instance, the nitrogen atom in (meth)acrylamide may be bonded to a hydrogen, or the hydrogen may be replaced with alkyl or cycloalkyl (which themselves may be further substituted).

Any type of free radical polymerization may be used including but not limited to bulk, solution, suspension, and emulsion as well as any of the controlled radical polymerization methods such as stable free radical polymerization, nitroxide-mediated living polymerization, atom transfer radical polymerization, reversible addition fragmentation chain transfer polymerization, organotellurium mediated living radical polymerization, and the like.

A “monomer” is a mono-functional molecule which can undergo chain growth polymerization, and in particular, free radical polymerization, thereby creating a repeating unit in the chemical structure of the target macromolecule. Some monomers have di-functional impurities that can act as cross-linking agents. A “hydrophilic monomer” is also a monomer which yields a clear single phase solution when mixed with deionized water at 25° C. at a concentration of 5 weight percent. A “hydrophilic component” is a monomer, macromer, prepolymer, initiator, cross-linker, additive, or polymer which yields a clear single phase solution when mixed with deionized water at 25° C. at a concentration of 5 weight percent. A “hydrophobic component” is a monomer, macromer, prepolymer, initiator, cross-linker, additive, or polymer which is slightly soluble or insoluble in deionized water at 25° C.

A “macromolecule” is an organic compound having a number average molecular weight of greater than 1500, and may be reactive or non-reactive.

A “macromonomer” or “macromer” is a macromolecule that has one group that can undergo chain growth polymerization, and in particular, free radical polymerization, thereby creating a repeating unit in the chemical structure of the target macromolecule. Typically, the chemical structure of the macromer is different than the chemical structure of the target macromolecule, that is, the repeating unit of the macromer's pendent group is different than the repeating unit of the target macromolecule or its mainchain. The difference between a monomer and a macromer is merely one of chemical structure, molecular weight, and molecular weight distribution of the pendent group. As a result, and as used herein, the patent literature occasionally defines monomers as polymerizable compounds having relatively low molecular weights of about 1,500 Daltons or less, which inherently includes some macromers. In particular, monomethacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxane (molecular weight=500-1500 g/mol) (mPDMS) and mono-(2-hydroxy-3-methacryloxypropyl)-propyl ether terminated mono-n-butyl terminated polydimethylsiloxane (molecular weight =500-1500 g/mol) (OH-mPDMS) may be referred to as monomers or macromers. Furthermore, the patent literature occasionally defines macromers as having one or more polymerizable groups, essentially broadening the common definition of macromer to include prepolymers. As a result and as used herein, di-functional and multi-functional macromers, prepolymers, and crosslinkers may be used interchangeably.

A “silicone-containing component” is a monomer, macromer, prepolymer, cross-linker, initiator, additive, or polymer in the reactive mixture with at least one silicon-oxygen bond, typically in the form of siloxy groups, siloxane groups, carbosiloxane groups, and mixtures thereof.

Examples of silicone-containing components which are useful in this invention may be found in U.S. Pat. Nos. 3,808,178, 4,120,570, 4,136,250, 4,153,641, 4,740,533, 5,034,461, 5,070,215, 5,244,981, 5,314,960, 5,331,067, 5,371,147, 5,760,100, 5,849,811, 5,962,548, 5,965,631, 5,998,498, 6,367,929, 6,822,016, 6,943,203, 6,951,894, 7,052,131, 7,247,692, 7,396,890, 7,461,937, 7,468,398, 7,538,146, 7,553,880, 7,572,841, 7,666,921, 7,691,916, 7,786,185, 7,825,170, 7,915,323, 7,994,356, 8,022,158, 8,163,206, 8,273,802, 8,399,538, 8,415,404, 8,420,711, 8,450,387, 8,487,058, 8,568,626, 8,937,110, 8,937,111, 8,940,812, 8,980,972, 9,056,878, 9,125,808, 9,140,825, 9,156,934, 9,170,349, 9,217,813, 9,244,196, 9,244,197, 9,260,544, 9,297,928, 9,297,929, and European Patent No. 080539. These patents are hereby incorporated by reference in their entireties.

A “polymer” is a target macromolecule composed of the repeating units of the monomers used during polymerization.

A “homopolymer” is a polymer made from one monomer; a “copolymer” is a polymer made from two or more monomers; a “terpolymer” is a polymer made from three monomers. A “block copolymer” is composed of compositionally different blocks or segments. Diblock copolymers have two blocks. Triblock copolymers have three blocks. “Comb or graft copolymers” are made from at least one macromer.

A “repeating unit” is the smallest group of atoms in a polymer that corresponds to the polymerization of a specific monomer or macromer.

An “initiator” is a molecule that can decompose into radicals which can subsequently react with a monomer to initiate a free radical polymerization reaction. A thermal initiator decomposes at a certain rate depending on the temperature; typical examples are azo compounds such as 1,1′-azobisisobutyronitrile and 4,4′-azobis(4-cyanovaleric acid), peroxides such as benzoyl peroxide, tert-butyl peroxide, tert-butyl hydroperoxide, tert-butyl peroxybenzoate, dicumyl peroxide, and lauroyl peroxide, peracids such as peracetic acid and potassium persulfate as well as various redox systems. A photo-initiator decomposes by a photochemical process; typical examples are derivatives of benzil, benzoin, acetophenone, benzophenone, camphorquinone, and mixtures thereof as well as various monoacyl and bisacyl phosphine oxides and combinations thereof.

A “cross-linking agent” is a di-functional or multi-functional monomer or macromer which can undergo free radical polymerization at two or more locations on the molecule, thereby creating branch points and a polymeric network. Common examples are ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, methylene bisacrylamide, triallyl cyanurate, and the like.

A “prepolymer” is a reaction product of monomers which contains remaining polymerizable groups capable of undergoing further reaction to form a polymer.

A “polymeric network” is a cross-linked macromolecule that can swell but cannot dissolve in solvents. “Hydrogels” are polymeric networks that swell in water or aqueous solutions, typically absorbing at least 10 weight percent water. “Silicone hydrogels” are hydrogels that are made from at least one silicone-containing component with at least one hydrophilic component. Hydrophilic components may also include non-reactive polymers.

“Conventional hydrogels” refer to polymeric networks made from components without any siloxy, siloxane or carbosiloxane groups. Conventional hydrogels are prepared from reactive mixtures comprising hydrophilic monomers. Examples include 2-hydroxyethyl methacrylate (“HEMA”), N-vinyl pyrrolidone (“NVP”), N, N-dimethylacrylamide (“DMA”) or vinyl acetate. U.S. Pat. Nos. 4,436,887, 4,495,313, 4,889,664, 5,006,622, 5,039459, 5,236,969, 5,270,418, 5,298,533, 5,824,719, 6,420,453, 6,423,761, 6,767,979, 7,934,830, 8,138,290, and 8,389,597 disclose the formation of conventional hydrogels. Commercially available conventional hydrogels include, but are not limited to, etafilcon, genfilcon, hilafilcon, lenefilcon, nesofilcon, omafilcon, polymacon, and vifilcon, including all of their variants.

“Silicone hydrogels” refer to polymeric networks made from at least one hydrophilic component and at least one silicone-containing component. Examples of silicone hydrogels include acquafilcon, asmofilcon, balafilcon, comfilcon, delefilcon, enfilcon, fanfilcon, formofilcon, galyfilcon, lotrafilcon, narafilcon, riofilcon, samfilcon, senofilcon, somofilcon, and stenfilcon, including all of their variants, as well as silicone hydrogels as prepared in U.S. Pat. Nos. 4,659,782, 4,659,783, 5,244,981, 5,314,960, 5,331,067, 5,371,147, 5,998,498, 6,087,415, 5,760,100, 5,776,999, 5,789,461, 5,849,811, 5,965,631, 6,367,929, 6,822,016, 6,867,245, 6,943,203, 7,247,692, 7,249,848, 7,553,880, 7,666,921, 7,786,185, 7,956,131, 8,022,158, 8,273,802, 8,399,538, 8,470,906, 8,450,387, 8,487,058, 8,507,577, 8,637,621, 8,703,891, 8,937,110, 8,937,111, 8,940,812, 9,056,878, 9,057,821, 9,125,808, 9,140,825, 9156,934, 9,170,349, 9,244,196, 9,244,197, 9,260,544, 9,297,928, 9,297,929 as well as WO 03/22321, WO 2008/061992, and US 2010/0048847. These patents are hereby incorporated by reference in their entireties.

An “interpenetrating polymeric network” comprises two or more networks which are at least partially interlaced on the molecular scale but not covalently bonded to each other and which cannot be separated without braking chemical bonds. A “semi-interpenetrating polymeric network” comprises one or more networks and one or more polymers characterized by some mixing on the molecular level between at least one network and at least one polymer. A mixture of different polymers is a “polymer blend.” A semi-interpenetrating network is technically a polymer blend, but in some cases, the polymers are so entangled that they cannot be readily removed.

The terms “reactive mixture” and “reactive monomer mixture” refer to the mixture of components (both reactive and non-reactive) which are mixed together and, when subjected to polymerization conditions, form the conventional or silicone hydrogels of the present invention as well as contact lenses made therefrom. The reactive monomer mixture may comprise reactive components such as the monomers, macromers, prepolymers, cross-linkers, and initiators, additives such as wetting agents, polymers, dyes, light absorbing compounds such as UV absorbers, pigments, dyes and photochromic compounds, any of which may be reactive or non-reactive but are capable of being retained within the resulting contact lens, as well as pharmaceutical and nutraceutical compounds, and any diluents. It will be appreciated that a wide range of additives may be added based upon the contact lens which is made and its intended use. Concentrations of components of the reactive mixture are expressed as weight percentages of all components in the reactive mixture, excluding diluent. When diluents are used, their concentrations are expressed as weight percentages based upon the amount of all components in the reactive mixture and the diluent.

“Reactive components” are the components in the reactive mixture which become part of the chemical structure of the polymeric network of the resulting hydrogel by covalent bonding, hydrogen bonding, electrostatic interactions, the formation of interpenetrating polymeric networks, or any other means.

The term “silicone hydrogel contact lens” refers to a hydrogel contact lens that is made from at least one silicone-containing compound. Silicone hydrogel contact lenses generally have increased oxygen permeability compared to conventional hydrogels. Silicone hydrogel contact lenses use both their water and polymer content to transmit oxygen to the eye.

The term “multi-functional” refers to a component having two or more polymerizable groups. The term “mono-functional” refers to a component having one polymerizable group.

The terms “halogen” or “halo” indicate fluorine, chlorine, bromine, and iodine.

“Alkyl” refers to an optionally substituted linear or branched alkyl group containing the indicated number of carbon atoms. If no number is indicated, then alkyl (including any optional substituents on alkyl) may contain 1 to 16 carbon atoms. Preferably, the alkyl group contains 1 to 10 carbon atoms, alternatively 1 to 8 carbon atoms, alternatively 1 to 6 carbon atoms, or alternatively 1 to 4 carbon atoms. Examples of alkyl include methyl, ethyl, propyl, isopropyl, butyl, iso-, sec- and tert-butyl, pentyl, hexyl, heptyl, 3-ethylbutyl, and the like. Examples of substituents on alkyl include 1, 2, or 3 groups independently selected from hydroxy, amino, amido, oxa, carboxy, alkyl carboxy, carbonyl, alkoxy, thioalkyl, carbamate, carbonate, halogen, phenyl, benzyl, and combinations thereof. “Alkylene” means a divalent alkyl group, such as —CH₂—, —CH₂CH₂—, —CH₂CH₂CH₂—, —CH₂CH(CH₃)CH₂—, and —CH₂CH₂CH₂CH₂—.

“Haloalkyl” refers to an alkyl group as defined above substituted with one or more halogen atoms, where each halogen is independently F, Cl, Br or I. A preferred halogen is F. Preferred haloalkyl groups contain 1-6 carbons, more preferably 1-4 carbons, and still more preferably 1-2 carbons. “Haloalkyl” includes perhaloalkyl groups, such as —CF₃— or —CF₂CF₃—. “Haloalkylene” means a divalent haloalkyl group, such as —CH₂CF₂—.

“Cycloalkyl” refers to an optionally substituted cyclic hydrocarbon containing the indicated number of ring carbon atoms. If no number is indicated, then cycloalkyl may contain 3 to 12 ring carbon atoms. Preferred are C₃-C₈ cycloalkyl groups, C₃-C₇ cycloalkyl, more preferably C₄-C₇ cycloalkyl, and still more preferably C₅-C₆ cycloalkyl. Examples of cycloalkyl include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. Examples of substituents on cycloalkyl include 1, 2, or 3 groups independently selected from alkyl, hydroxy, amino, amido, oxa, carbonyl, alkoxy, thioalkyl, amido, carbamate, carbonate, halo, phenyl, benzyl, and combinations thereof. “Cycloalkylene” means a divalent cycloalkyl group, such as 1,2-cyclohexylene, 1,3- cyclohexylene, or 1,4-cyclohexylene.

“Heterocycloalkyl” refers to a cycloalkyl ring or ring system as defined above in which at least one ring carbon has been replaced with a heteroatom selected from nitrogen, oxygen, and sulfur. The heterocycloalkyl ring is optionally fused to or otherwise attached to other heterocycloalkyl rings and/or non-aromatic hydrocarbon rings and/or phenyl rings. Preferred heterocycloalkyl groups have from 5 to 7 members. More preferred heterocycloalkyl groups have 5 or 6 members. Heterocycloalkylene means a divalent heterocycloalkyl group.

“Aryl” refers to an optionally substituted aromatic hydrocarbon ring system containing at least one aromatic ring. The aryl group contains the indicated number of ring carbon atoms. If no number is indicated, then aryl may contain 6 to 14 ring carbon atoms. The aromatic ring may optionally be fused or otherwise attached to other aromatic hydrocarbon rings or non-aromatic hydrocarbon rings. Examples of aryl groups include phenyl, naphthyl, and biphenyl. Preferred examples of aryl groups include phenyl. Examples of substituents on aryl include 1, 2, or 3 groups independently selected from alkyl, hydroxy, amino, amido, oxa, carboxy, alkyl carboxy, carbonyl, alkoxy, thioalkyl, carbamate, carbonate, halo, phenyl, benzyl, and combinations thereof. “Arylene” means a divalent aryl group, for example 1,2-phenylene, 1,3-phenylene, or 1,4-phenylene.

“Heteroaryl” refers to an aryl ring or ring system, as defined above, in which at least one ring carbon atom has been replaced with a heteroatom selected from nitrogen, oxygen, and sulfur. The heteroaryl ring may be fused or otherwise attached to one or more heteroaryl rings, aromatic or nonaromatic hydrocarbon rings or heterocycloalkyl rings. Examples of heteroaryl groups include pyridyl, furyl, and thienyl. “Heteroarylene” means a divalent heteroaryl group.

“Alkoxy” refers to an alkyl group attached to the parent molecular moiety through an oxygen bridge. Examples of alkoxy groups include, for instance, methoxy, ethoxy, propoxy and isopropoxy. “Thioalkyl” means an alkyl group attached to the parent molecule through a sulfur bridge. Examples of thioalkyl groups include, for instance, methylthio, ethylthio, n-propylthio and iso-propylthio. “Aryloxy” refers to an aryl group attached to a parent molecular moiety through an oxygen bridge. Examples include phenoxy. “Cyclic alkoxy” means a cycloalkyl group attached to the parent moiety through an oxygen bridge.

“Alkylamine” refers to an alkyl group attached to the parent molecular moiety through an —NH bridge. Alkyleneamine means a divalent alkylamine group, such as —CH₂CH₂NH—.

“Siloxanyl” refers to a structure having at least one Si—O—Si bond. Thus, for example, siloxanyl group means a group having at least one Si—O—Si group (i.e. a siloxane group), and siloxanyl compound means a compound having at least one Si—O—Si group. “Siloxanyl” encompasses monomeric (e.g., Si—O—Si) as well as oligomeric/polymeric structures (e.g., —[Si—O]_(n)—, where n is 2 or more). Each silicon atom in the siloxanyl group is substituted with independently selected R^(A) groups (where R^(A) is as defined in formula A options (b)-(i)) to complete their valence.

“Silyl” refers to a structure of formula R₃Si— and “siloxy” refers to a structure of formula R₃Si—O—, where each R in silyl or siloxy is independently selected from trimethylsiloxy, C₁-C₈ alkyl (preferably C₁-C₃ alkyl, more preferably ethyl or methyl), and C₃-C₈ cycloalkyl.

“Alkyleneoxy” refers to groups of the general formula —(alkylene—O)_(p)— or —(O—alkylene)_(p)—, wherein alkylene is as defined above, and p is from 1 to 200, or from 1 to 100, or from 1 to 50, or from 1 to 25, or from 1 to 20, or from 1 to 10, wherein each alkylene is independently optionally substituted with one or more groups independently selected from hydroxyl, halo (e.g., fluoro), amino, amido, ether, carbonyl, carboxyl, and combinations thereof. If p is greater than 1, then each alkylene may be the same or different and the alkyleneoxy may be in block or random configuration. When alkyleneoxy forms a terminal group in a molecule, the terminal end of the alkyleneoxy may, for instance, be a hydroxy or alkoxy (e.g., HO—[CH₂CH₂O]_(p)— or CH₃O—[CH₂CH₂O]_(p)—). Examples of alkyleneoxy include polyethyleneoxy, polypropyleneoxy, polybutyleneoxy, and poly(ethyleneoxy-co-propyleneoxy).

“Oxaalkylene” refers to an alkylene group as defined above where one or more non-adjacent CH₂ groups have been substituted with an oxygen atom, such as —CH₂CH₂OCH(CH₃)CH₂—. “Thiaalkylene” refers to an alkylene group as defined above where one or more non-adjacent CH₂ groups have been substituted with a sulfur atom, such as —CH₂CH₂SCH(CH₃)CH₂—.

The term “linking group” refers to a moiety that links a polymerizable group to the parent molecule. The linking group may be any moiety that is compatible with the compound of which it is a part, and that does not undesirably interfere with the polymerization of the compound , is stable under the polymerization conditions as well as the conditions for the processing and storage of the final product. For instance, the linking group may be a bond, or it may comprise one or more alkylene, haloalkylene, amide, amine, alkyleneamine, carbamate, ester (—CO₂—), arylene, heteroarylene, cycloalkylene, heterocycloalkylene, alkyleneoxy, oxaalkylene, thiaalkylene, haloalkyleneoxy (alkyleneoxy substituted with one or more halo groups, e.g., —OCF₂—, —OCF₂CF₂—, —OCF₂CH₂—), siloxanyl, alkylenesiloxanyl, or combinations thereof. The linking group may optionally be substituted with 1 or more substituent groups. Suitable substituent groups may include those independently selected from alkyl, halo (e.g., fluoro), hydroxyl, HO-alkyleneoxy, MeO-alkyleneoxy, siloxanyl, siloxy, siloxy-alkyleneoxy-, siloxy-alkylene-alkyleneoxy- (where more than one alkyleneoxy groups may be present and wherein each methylene in alkylene and alkyleneoxy is independently optionally substituted with hydroxyl), ether, amine, carbonyl, carbamate, and combinations thereof. The linking group may also be substituted with a polymerizable group, such as (meth)acrylate (in addition to the polymerizable group to which the linking group is linked).

Preferred linking groups include C₁-C₈ alkylene (preferably C₂-C₆ alkylene) and C₁-C₈ oxaalkylene (preferably C₂-C₆ oxaalkylene), each of which is optionally substituted with 1 or 2 groups independently selected from hydroxyl and siloxy. Preferred linking groups also include carboxylate, amide, C₁-C₈ alkylene-carboxylate-C₁-C₈ alkylene, or C₁-C₈ alkylene-amide-C₁-C₈ alkylene.

When the linking group is comprised of combinations of moieties as described above (e.g., alkylene and cycloalkylene), the moieties may be present in any order. For instance, if in Formula E below, L is indicated as being -alkylene-cycloalkylene-, then Rg-L may be either Rg-alkylene-cycloalkylene-, or Rg-cycloalkylene-alkylene-. Notwithstanding this, the listing order represents the preferred order in which the moieties appear in the compound starting from the terminal polymerizable group (Rg or Pg) to which the linking group is attached. For example, if in Formula E, L and L² are indicated as both being alkylene-cycloalkylene, then Rg-L is preferably Rg-alkylene-cycloalkylene- and -L²-Rg is preferably -cycloalkylene-alkylene-Rg.

The term “electron withdrawing group” (EWG) refers to a chemical group which withdraws electron density from the atom or group of atoms to which the electron withdrawing group is attached. Examples of EWGs include, but are not limited to, cyano, amide, ester, keto, or aldehyde. A preferred EWG is cyano (CN).

The terms “high energy visible light absorbing compound” or “HEV light absorbing compound” refer to chemical materials that absorb one or more wavelengths of high energy visible light, for instance in the range of 400 to 450 nm. A material's ability to absorb certain wavelengths of light can be determined by measuring its UV/Vis transmission spectrum. Compounds that exhibit no absorption at a particular wavelength will exhibit substantially 100 percent transmission at that wavelength. Conversely, compounds that completely absorb at a particular wavelength will exhibit substantially 0% transmission at that wavelength. As used herein, if the amount of a contact lens's transmission is indicated as a percentage across a particular wavelength range, it is to be understood that the contact lens exhibits the percent transmission at all wavelengths across that range. For purposes of the invention, a material that has a transmission of greater than 90 percent across the wavelength range of 400 to 450 nm is not an HEV light absorbing compound.

The terms “photostable,” “photostability,” or similar expressions mean that a contact lens (containing an HEV light absorbing compound) doesn't exhibit a substantial change in its visible light transmission spectrum after exposure to light, when packaged in a clear blister pack, under conditions of the International Conference on Harmonisation (ICH) of Technical Requirements for Registration of Pharmaceuticals for Human Use guideline, Q1B Photostability Testing of New Drug Substances and Products, published on November 1996. Preferably, the exposure is conducted under the ICH Photostability Guideline using an Option 2 light source with an estimated illuminance exposure of 1.5192×10⁶ Lux hours (168.8 hours exposure time) and an estimated ultraviolet irradiation exposure of 259.4 Watt hours/m² (16.2 hours exposure time), preferably in a photostability chamber that is controlled at 25° C/Amb RH. When lenses are measured within a blister pack, the blister pack is exposed foil side down to maximize irradiance from the light source during photo exposure. After exposure, the UV/Vis spectrum of the test lens is collected and compared to a control lens (a lens that was not subjected to Q1B conditions). Photostability may be represented as the percent change in average transmission of the test lens relative to the control lens at a selected wavelength range. The change may be calculated as the absolute value of the difference in the average transmission (over the selected wavelength range) between the control lens and the test lens, divided by the average transmission of the control lens (at the selected wavelength range). For purposes of the invention, a contact lens is considered to be photostable if the change in average transmission over the selected wavelength range (e.g., 380 to 450 nm) is 20 percent or less, or 15 percent or less, or 10 percent or less, or 7 percent or less, or 5 percent or less, or 2 percent or less. The measurement may, for instance, be made on a −1.00 diopter contact lens.

The term “photochromic compound” refers to a material which reversibly changes its absorption properties (i.e., color) caused by a photochemical reaction within the material upon exposure to specific wavelengths of electromagnetic radiation. By way of example, a photochromic compound may exhibit a reversible change in average transmission of 5% or more, or 10% or more, or 20% percent or more, in the visible portion of the electromagnetic spectrum (e.g., in the wavelength range of about 380 nm to about 760 nm) when exposed to UV or HEV light. A “static compound” is a material that is not photochromic, thus the material does not undergo a photochemical reaction that reversibly changes its transmission.

The term “multifocal” encompasses any type of intraocular or contact lens that is designed for presbyopic patients. For instance, the term encompasses any type of multifocal contact lens designed for presbyopic patients including, without limitation, bifocal contact lenses, trifocal contact lenses, translating lenses, and lenses containing concentric rings, aspheric designs, or extended depth of focus designs, as well as diffractive designs. For instance, a multifocal contact lens, with or without astigmatic correction, may contain a region in which the power continuously increases from distance to near optical power or continuously decreases from near to distance optical power from the lens center and radially toward the edge of the optical zone. A multifocal lens may address vision issues other than presbyopia. For instance, the lens may also be a toric lens for patients that are both presbyopic and astigmatic.

Unless otherwise indicated, ratios, percentages, parts, and the like are by weight.

Unless otherwise indicated, numeric ranges, for instance as in “from 2 to 10,” are inclusive of the numbers defining the range (e.g., 2 and 10).

As noted above, one aspect the invention provides a multifocal contact lens that is a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible (HEV) light absorbing compound.

The contact lens may transmit from 0 percent to 70 percent, or from 1 to 70 percent, of light across a wavelength range of 400 to 409 nm. The transmission of the contact lens across the 400 to 409 nm wavelength range may be at least 2 percent, or at least 3 percent, or at least 4 percent. The transmission of the contact lens across the 400 to 409 nm range may be up to 60 percent, or up to 50 percent, or up to 40 percent, or up to 30 percent, or up 20 percent.

The contact lens may transmit 10 percent or less of light across a wavelength range of 200 to 279 nm. The transmission of the contact lens across the 200 to 279 nm wavelength range may be 5 percent or less or 1 percent or less, or less than 1 percent.

The contact lens may transmit 45 percent or less of light across a wavelength range of 280 to 399 nm. The transmission of the contact lens across 280 to 399 nm wavelength range may be 35 percent or less, or 25 percent or less, or 20 percent or less, or 10 percent or less, or 5 percent or less, or 1 percent or less.

The contact lens may transmit at least 10 percent of light across a wavelength range of 410 to 424 nm. The transmission of the contact lens across the 410 to 424 nm wavelength range may be at least 15 percent. The transmission of the contact lens across the 410 to 424 nm wavelength range may be up to 95 percent, up to 85 percent, up to 75 percent, or up 65 percent.

The contact lens may transmit at least 50 percent of light across a wavelength range of 425 to 449 nm. The transmission of the contact lens across the 425 to 449 nm range may be at least 60 percent.

The contact lens may transmit at least 80 percent of light across a wavelength range of 450 to 800 nm. The transmission of the contact lens across the 450 to 800 nm wavelength range may be at least 85 percent.

The contact lens may transmit from 1 to 70 percent of light across a wavelength range of 400 to 409 nm; and 45 percent or less of light across a wavelength range of 280 to 399 nm.

The contact lens may transmit from 1 to 70 percent of light across a wavelength range of 400 to 409 nm; 45 percent or less of light across a wavelength range of 280 to 399 nm; and at least 80 percent of light across a wavelength range of 450 to 800 nm.

The contact lens may transmit from 1 to 70 percent of light across a wavelength range of 400 to 409 nm; 45 percent or less of light across a wavelength range of 280 to 399 nm; from 10 to 95 percent of light across a wavelength range of 410 to 424 nm; at least 50 percent of light across a wavelength range of 425 to 449 nm; and at least 80 percent of light across a wavelength range of 450 to 800 nm.

The contact lens may be a soft hydrogel contact lens, preferably a silicone hydrogel contact lens. The foregoing transmission wavelengths and percentages may be measured on various thicknesses of lenses. For example, the center thickness may be from 70 to 300 microns, or from 80 to 230 microns, or from 80 to 110 microns, or from 90 to 110 microns. The concentration of the one or more high energy visible light absorbing compounds may be adjusted to achieve the foregoing transmission properties. For instance, the concentration may be in the range of at least 0.01 percent, or at least 0.1 percent, or at least 1 percent, or at least 2 percent; and up to 10 percent or up to 5 percent, based on the weight percentages of all components in the reactive mixture, excluding diluent. A typical concentration may be in the range of 1 to 5 percent.

The HEV light absorbing compound for use in the multifocal contact lenses of the invention may be a compound of formula I:

wherein:

-   -   m and n are independently 0, 1, 2, 3, or 4;     -   T is a bond, O, or NR;     -   Y is a linking group;     -   P_(g) is a polymerizable group;     -   R at each occurrence is independently H, C₁-C₆ alkyl,         cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or Y-P_(g); and     -   R¹ and R², when present, are independently at each occurrence         C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ thioalkyl, C₃-C₇ cycloalkyl,         aryl (preferably unsubstituted phenyl or phenyl substituted with         alkyl or halo), halo, hydroxy, amino, NR³R⁴, or benzyl, wherein         R³ and R⁴ are independently H or C₁-C₆ alkyl, or two adjacent R¹         or R² groups, together with the carbon atoms to which they are         attached, combine to form a cycloalkyl or aryl ring. Compounds         of formula I preferably contain one or two Y-P_(g) groups. More         preferably, the compounds contain one Y-P_(g) group.

I-1. Compounds of formula I may include compounds of formula I-1, which are compounds of formula I wherein m and n are independently 0 or 1, or alternatively both are 0.

I-2. Compounds of formulae I and I-1 may include compounds of formula I-2, which are compounds of formula I, or I-1 wherein m is 1 and R¹ is C₁-C₆ alkyl, preferably ethyl or methyl.

I-3. Compounds of formulae I, I-1, and I-2 may include compounds of formula I-3, which are compounds of formula I, I-1, or I-2 wherein n is 1 and R² is C₁-C₆ alkyl, preferably ethyl or methyl.

I-4. Compounds of formulae I, I-1, I-2, and I-3 may include compounds of formula I-4, which are compounds of formula I, I-1, I-2, or I-3 wherein R is H, or C₁-C₆ alkyl. Preferably, R in the group T is H.

I-5. Compounds of formulae I, I-1, I-2, I-3, and I-4 may include compounds of formula I-5, which are compounds of formula I, I-1, I-2, I-3, or I-4 wherein P_(g) (a polymerizable group) at each occurrence independently comprises styryl, vinyl carbonate, vinyl ether, vinyl carbamate, N-vinyl lactam, N-vinylamide, (meth)acrylate, or (meth)acrylamide. The polymerizable group allows the compounds of the invention to form covalent bonds when reacted with monomers, crosslinking agents, and other components generally used in making contact lenses. The compatibility of the compounds with the reactive mixture can be controlled via the selection of the polymerizable group (and the linking group). Preferred polymerizable groups include (meth)acrylate or (meth)acrylamide. A more preferred polymerizable group is methacrylate.

I-6. Compounds of formulae I, I-1, I-2, I-3, I-4, and I-5 may include compounds of formula I-6, which are compounds of formula I, I-1, I-2, I-3, I-4, or I-5 wherein Y (a linking group) is alkylene, cycloalkylene, heterocycloalkylene, arylene (e.g., phenylene), heteroarylene, oxaalkylene, alkylene-amide-alkylene, alkylene-amine-alkylene, or combinations of any of the foregoing groups. Preferred linking groups include C₁-C₈ alkylene (e.g., ethylene or propylene), C₁-C₈ oxaalkylene, C₁-C₈ alkylene-amide-C₁-C₈ alkylene, and C₁-C₈ alkylene-amine-C₁-C₈ alkylene. Particularly preferred is C₁-C₈ alkylene, especially ethylene (—CH₂CH₂—). When T in the compound of formula I is O, it is preferred that the carbon atom of the linking group to which the O is attached be hindered. For instance, if T is O and Y is alkylene, a preferred alkylene is —C(R^(H))₂(CH₂)_(x)—, where R^(H) is independently C₁-C₆ alkyl (preferably independently methyl or ethyl) and x is from 1 to 5.

I-7. Compounds of formulae I, I-1, I-2, I-3, I-4, I-5, and I-6 may include compounds of formula I-7, which are compounds of formula I, I-1, I-2, I-3, I-4, I-5, or I-6 wherein T is a bond or is NR (preferably NH).

Compounds of formula I may include compounds of formula II:

wherein:

-   -   m and n are independently 0, 1, 2, 3, or 4;     -   Y is a linking group;     -   P_(g) is a polymerizable group;     -   R at each occurrence is independently H, C₁-C₆ alkyl,         cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or Y-P_(g); and     -   R¹ and R², when present, are independently at each occurrence         C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ thioalkyl, C₃-C₇ cycloalkyl,         aryl (preferably unsubstituted phenyl or phenyl substituted with         alkyl or halo), halo, hydroxy, amino, NR³R⁴, or benzyl, wherein         R³ and R⁴ are independently H or C₁-C₆ alkyl, or two adjacent R¹         or R² groups, together with the carbon atoms to which they are         attached, combine to form a cycloalkyl or aryl ring. Compounds         of formula II preferably contain one or two Y-P_(g) groups. More         preferably, the compounds contain one Y-P_(g) group.

II-1. Compounds of formulae II may include compounds of formula II-1, which are compounds of formula II wherein m and n are independently 0 or 1, or alternatively both are 0.

II-2. Compounds of formulae II, and II-1 may include compounds of formula II-2, which are compounds of formula II, or II-1 wherein m is 1 and R¹ is C₁-C₆ alkyl, preferably ethyl or methyl.

II-3. Compounds of formulae II, II-1, and II-2 may include compounds of formula II-3, which are compounds of formula II, II-1, or II-2 wherein n is 1 and R² is C₁-C₆ alkyl, preferably ethyl or methyl.

II-4. Compounds of formulae II, II-1, II-2, and II-3 may include compounds of formula II-4, which are compounds of formula II, II-1, II-2, or II-3 wherein Rat each occurrence is independently H, or C₁-C₆ alkyl. Preferably, R at each occurrence is H. Preferably R in the group T is H.

II-5. Compounds of formulae II, II-1, II-2, II-3, and II-4 may include compounds of formula II-5, which are compounds of formula II, II-1, II-2, II-3, or II-4 wherein P_(g) (a polymerizable group) at each occurrence independently comprises styryl, vinyl carbonate, vinyl ether, vinyl carbamate, N-vinyl lactam, N-vinylamide, (meth)acrylate, or (meth)acrylamide. The polymerizable group allows the compounds of the invention to form covalent bonds when reacted with monomers, crosslinking agents, and other components generally used in making polymeric devices. The compatibility of the compounds with the reactive mixture can be controlled via the selection of the polymerizable group (and the linking group). Preferred polymerizable groups include (meth)acrylate or (meth)acrylamide. A more preferred polymerizable group is methacrylate.

II-6. Compounds of formulae II, II-1, II-2, II-3, II-4, and II-5 may include compounds of formula II-6, which are compounds of formula II, II-1, II-2, II-3, II-4, or II-5 wherein Y (a linking group) is alkylene, cycloalkylene, heterocycloalkylene, arylene (e.g., phenylene), heteroarylene, oxaalkylene, alkylene-amide-alkylene, alkylene-amine-alkylene, or combinations of any of the foregoing groups. Preferred linking groups include C₁-C₈ alkylene (e.g., ethylene or propylene), C₁-C₈ oxaalkylene, C₁-C₈ alkylene-amide-C₁-C₈ alkylene, and C₁-C₈ alkylene-amine-C₁-C₈ alkylene. Particularly preferred is C₁-C₈ alkylene, especially ethylene (—CH₂CH₂—).

Specific examples of compounds of formula I include, but are not limited to, the compounds shown in Table 1.

TABLE 1

2-(2-cyano-2-(9H-thioxanthen-9- ylidene)acetamido)ethyl methacrylate

2-(2-cyano-2-(9H-thioxanthen-9- ylidene)acetamido)ethyl acrylate

N-(2-(2-cyano-2-(9H-thioxanthen-9- ylidene)acetamido)ethyl)methacrylamide

N-(2-(2-cyano-2-(9H-thioxanthen-9- ylidene)acetamido)ethyl)acrylamide

2-(2-cyano-N-methyl-2-(9H-thioxanthen-9- ylidene)acetamido)ethyl methacrylate

2-cyano-2-(9H-thioxanthen-9-ylidene)-N-(2-(N- vinylacetamido)ethyl)acetamide

2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)- 2-methylpropyl methacrylate

(E)-2-(2-cyano-2-(2,4-dichloro-9H-thioxanthen-9- ylidene)acetamido)ethyl methacrylate

(E)-2-(2-(2-chloro-9H-thioxanthen-9-ylidene)-2- cyanoacetamido)ethyl methacrylate

(E)-2-(2-cyano-2-(2-isopropyl-9H-thioxanthen-9- ylidene)acetamido)ethyl methacrylate

(E)-2-(2-cyano-2-(4-isopropyl-9H-thioxanthen-9- ylidene)acetamido)ethyl methacrylate

2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetoxy)ethyl methacrylate

High energy visible (HEV) light absorbing compounds for use in the invention are preferably photostable. Thus, contact lenses of the invention, containing HEV light absorbing compounds, preferably exhibit 20% or less, alternatively 15% or less, alternatively 10% or less, alternatively 7% or less, alternatively 5% or less, or alternatively 2% or less of change in their average transmission over a wavelength range of 380 to 450 nm, following exposure under ICH Q1B conditions, compared to a control lens.

Contact lenses of the invention may comprise other absorbing compounds, in addition to HEV light absorbing compounds, to provide desirable absorption characteristics. For example, preferred compositions may comprise an HEV light absorbing compound and a compound that absorbs UV. Suitable UV absorbing compounds are known in the art, and fall into several classes which include, but are not limited to, benzophenones, benzotriazoles, triazines, substituted acrylonitriles, salicyclic acid derivatives, benzoic acid derivatives, cinnamic acid derivatives, chalcone derivatives, dypnone derivatives, crotonic acid derivatives, or any mixtures thereof. A preferred class of UV absorbing compound is benzotriazoles, such as Norbloc (2-(2′-hydroxy-5-methacrylyloxyethylphenyl)-2H-benzotriazole).

A particularly preferred composition comprises 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate and a UV absorbing compound, such as a benzotriazole, for instance (2-(2′-hydroxy-5-methacrylyloxyethylphenyl)-2H-benzotriazole).

Compounds of formula I may be prepared by those skilled in the art using literature methods. By way of example, various compounds of formula I may be prepared as shown in Scheme 1 and the associated description. Exemplary reagents and procedures for these reactions appear in the working examples.

Scheme 1 shows a method for preparing exemplary compounds of the invention. Thus, the carbonyl moiety of the starting material is converted to a reactive dihalide intermediate, which is further reacted with the active methylene compound without further purification or isolation. The reaction mixture is protected from air and moisture until completion of the reaction with the cyanomethyl amide derivative. Other compounds of the invention may be prepared by those skilled in the art using analogous procedures to those shown in Scheme 1 with appropriate substitution of reagents.

High energy visible light absorbing compounds, such as the compounds of formula I, may be included in reactive mixtures to form contact lenses. Generally, the high energy visible light absorbing compounds can be present in any amount, typically up to the limit of their solubility. For instance, the compounds may be present in an amount in the range of about 0.1% to about 10% by weight, or from about 0.5 to about 5% by weight, or from about 0.75% to about 4% by weight. The upper limit is typically determined by the solubility of the compound with other co-monomers and or diluents in the reactive monomer mix.

A variety of contact lenses may be prepared, including hard contact lenses and soft contact lenses. Preferably, the contact lens is a soft contact lens, which may be made from conventional or silicone hydrogel formulations. In addition to being multifocal, the contact lens may also be toric. Thus, the contact lens of the invention may be a multifocal toric contact lens.

Contact lenses of the invention comprise a free radical reaction product of a reactive mixture containing one or more high energy visible (HEV) light absorbing compounds, such as compounds of formula I, one or more polymerizable compounds suitable for making the desired ophthalmic device (also referred to herein as device forming polymerizable compounds or hydrogel forming polymerizable compounds), and optional components. Thus, the reactive mixture may, for example, include, in addition to a high energy visible light absorbing compound as described above, one or more of: hydrophilic components, hydrophobic components, silicone-containing components, wetting agents such as polyamides, crosslinking agents, and further components such as diluents and initiators.

Hydrophilic Components

Examples of suitable families of hydrophilic monomers include (meth)acrylates, styrenes, vinyl ethers, (meth)acrylamides, N-vinyl lactams, N-vinyl amides, N-vinyl imides, N-vinyl ureas, O-vinyl carbamates, O-vinyl carbonates, other hydrophilic vinyl compounds, and mixtures thereof.

Non-limiting examples of hydrophilic (meth)acrylate and (meth)acrylamide monomers include: acrylamide, N-isopropyl acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, N,N-dimethyl acrylamide (DMA), 2-hydroxyethyl methacrylate (HEMA), 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, N-(2-hydroxyethyl) (meth)acrylamide, N,N-bis(2-hydroxyethyl) (meth)acrylamide, N-(2-hydroxypropyl) (meth)acrylamide, N,N-bis(2-hydroxypropyl) (meth)acrylamide, N-(3-hydroxypropyl) (meth)acrylamide, N-(2-hydroxybutyl) (meth)acrylamide, N-(3-hydroxybutyl) (meth)acrylamide, N-(4-hydroxybutyl) (meth)acrylamide, 2-aminoethyl (meth)acrylate, 3-aminopropyl (meth)acrylate, 2-aminopropyl (meth)acrylate, N-2-aminoethyl (meth)acrylamides), N-3-aminopropyl (meth)acrylamide, N-2-aminopropyl (meth)acrylamide, N,N-bis-2-aminoethyl (meth)acrylamides, N,N-bis-3-aminopropyl (meth)acrylamide), N,N-bis-2-aminopropyl (meth)acrylamide, glycerol methacrylate, polyethyleneglycol monomethacrylate, (meth)acrylic acid, vinyl acetate, acrylonitrile, and mixtures thereof.

Hydrophilic monomers may also be ionic, including anionic, cationic, zwitterions, betaines, and mixtures thereof. Non-limiting examples of such charged monomers include (meth)acrylic acid, N-[(ethenyloxy)carbonyl]-O-alanine (VINAL), 3-acrylamidopropanoic acid (ACA1), 5-acrylamidopentanoic acid (ACA2), 3-acrylamido-3-methylbutanoic acid (AMBA), 2-(methacryloyloxy)ethyl trimethylammonium chloride (Q Salt or METAC), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), 1-propanaminium, N-(2-carboxyethyl)-N,N-dimethyl-3-[(1-oxo-2-propen-1-yl)amino]-, inner salt (CBT), 1-propanaminium, N,N-dimethyl-N-[3-[(1-oxo-2-propen-1-yl)amino]propyl]-3-sulfo-, inner salt (SBT), 3,5-Dioxa-8-aza-4-phosphaundec-10-en-1-aminium, 4-hydroxy-N,N,N-trimethyl-9-oxo-, inner salt, 4-oxide (9CI) (PBT), 2-methacryloyloxyethyl phosphorylcholine, 3-(dimethyl(4-vinylbenzyl)ammonio)propane-1-sulfonate (DMVBAPS), 3-((3-acrylamidopropyl)dimethylammonio)propane-1-sulfonate (AMPDAPS), 3-((3-methacrylamidopropyl)dimethylammonio)propane-1-sulfonate (MAMPDAPS), 3-((3-(acryloyloxy)propyl)dimethylammonio)propane-1-sulfonate (APDAPS), and methacryloyloxy)propyl)dimethylammonio)propane-1-sulfonate (MAPDAPS).

Non-limiting examples of hydrophilic N-vinyl lactam and N-vinyl amide monomers include: N-vinyl pyrrolidone (NVP), N-vinyl-2-piperidone, N-vinyl-2-caprolactam, N-vinyl-3-methyl-2-caprolactam, N-vinyl-3-methyl-2-piperidone, N-vinyl-4-methyl-2-piperidone, N-vinyl-4-methyl-2-caprolactam, N-vinyl-3-ethyl-2- pyrrolidone, N-vinyl-4,5-dimethyl-2-pyrrolidone, N-vinyl acetamide (NVA), N-vinyl-N-methylacetamide (VMA), N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide, N-vinyl-N-methylpropionamide, N-vinyl-N-methyl-2-methylpropionamide, N-vinyl-2-methylpropionamide, N-vinyl-N,N′-dimethylurea, 1-methyl-3-methylene-2-pyrrolidone, 1-methyl-5-methylene-2-pyrrolidone, 5-methyl-3-methylene-2-pyrrolidone; 1-ethyl-5-methylene-2-pyrrolidone, N-methyl-3-methylene-2-pyrrolidone, 5-ethyl-3-methylene-2-pyrrolidone, 1-N-propyl-3-methylene-2-pyrrolidone, 1-N-propyl-5-methylene-2-pyrrolidone, 1-isopropyl-3-methylene-2-pyrrolidone, 1-isopropyl-5-methylene-2-pyrrolidone, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, N-vinyl formamide, N-vinyl isopropylamide, N-vinyl caprolactam, N-vinylimidazole, and mixtures thereof.

Non-limiting examples of hydrophilic O-vinyl carbamates and O-vinyl carbonates monomers include N-2-hydroxyethyl vinyl carbamate and N-carboxy-B-alanine N-vinyl ester. Further examples of hydrophilic vinyl carbonate or vinyl carbamate monomers are disclosed in U.S. Pat. No. 5,070,215. Hydrophilic oxazolone monomers are disclosed in U.S. Pat. No. 4,910,277.

Other hydrophilic vinyl compounds include ethylene glycol vinyl ether (EGVE), di(ethylene glycol) vinyl ether (DEGVE), allyl alcohol, and 2-ethyl oxazoline.

The hydrophilic monomers may also be macromers or prepolymers of linear or branched poly(ethylene glycol), poly(propylene glycol), or statistically random or block copolymers of ethylene oxide and propylene oxide, having polymerizable moieties such as (meth)acrylates, styrenes, vinyl ethers, (meth)acrylamides, N-vinylamides, and the like. The macromers of these polyethers have one polymerizable group; the prepolymers may have two or more polymerizable groups.

The preferred hydrophilic monomers of the present invention are DMA, NVP, HEMA, VMA, NVA, and mixtures thereof. Preferred hydrophilic monomers include mixtures of DMA and HEMA. Other suitable hydrophilic monomers will be apparent to one skilled in the art.

Generally, there are no particular restrictions with respect to the amount of the hydrophilic monomer present in the reactive monomer mixture. The amount of the hydrophilic monomers may be selected based upon the desired characteristics of the resulting hydrogel, including water content, clarity, wettability, protein uptake, and the like. Wettability may be measured by contact angle, and desirable contact angles are less than about 100°, less than about 80°, and less than about 60°. The hydrophilic monomer may be present in an amount in the range of, for instance, about 0.1 to about 100 weight percent, alternatively in the range of about 1 to about 80 weight percent, alternatively about 5 to about 65 weight percent, alternatively in the range of about 40 to about 60 weight percent, or alternatively about 55 to about 60 weight percent, based on the total weight of the reactive components in the reactive monomer mixture.

Silicone-Containing Components

Silicone-containing components suitable for use in the invention comprise one or more polymerizable compounds, where each compound independently comprises at least one polymerizable group, at least one siloxane group, and one or more linking groups connecting the polymerizable group(s) to the siloxane group(s). The silicone-containing components may, for instance, contain from 1 to 220 siloxane repeat units, such as the groups defined below. The silicone-containing component may also contain at least one fluorine atom.

The silicone-containing component may comprise: one or more polymerizable groups as defined above; one or more optionally repeating siloxane units; and one or more linking groups connecting the polymerizable groups to the siloxane units. The silicone-containing component may comprise: one or more polymerizable groups that are independently a (meth)acrylate, a styryl, a vinyl ether, a (meth)acrylamide, an N-vinyl lactam, an N-vinylamide, an O-vinylcarbamate, an O-vinylcarbonate, a vinyl group, or mixtures of the foregoing; one or more optionally repeating siloxane units; and one or more linking groups connecting the polymerizable groups to the siloxane units.

The silicone-containing component may comprise: one or more polymerizable groups that are independently a (meth)acrylate, a (meth)acrylamide, an N-vinyl lactam, an N-vinylamide, a styryl, or mixtures of the foregoing; one or more optionally repeating siloxane units; and one or more linking groups connecting the polymerizable groups to the siloxane units.

The silicone-containing component may comprise: one or more polymerizable groups that are independently a (meth)acrylate, a (meth)acrylamide, or mixtures of the foregoing; one or more optionally repeating siloxane units; and one or more linking groups connecting the polymerizable groups to the siloxane units.

Formula A. The silicone-containing component may comprise one or more polymerizable compounds of Formula A:

wherein:

-   -   at least one R^(A) is a group of formula R_(g)-L- wherein R_(g)         is a polymerizable group and L is a linking group, and the         remaining R^(A) are each independently:         -   (a) R_(g)-L-,         -   (b) C₁-C₁₆ alkyl optionally substituted with one or more             hydroxy, amino, amido, oxa, carboxy, alkyl carboxy,             carbonyl, alkoxy, amido, carbamate, carbonate, halo, phenyl,             benzyl, or combinations thereof,         -   (c) C₃-C₁₂ cycloalkyl optionally substituted with one or             more alkyl, hydroxy, amino, amido, oxa, carbonyl, alkoxy,             amido, carbamate, carbonate, halo, phenyl, benzyl, or             combinations thereof,         -   (d) a C₆-C₁₄ aryl group optionally substituted with one or             more alkyl, hydroxy, amino, amido, oxa, carboxy, alkyl             carboxy, carbonyl, alkoxy, amido, carbamate, carbonate,             halo, phenyl, benzyl, or combinations thereof,         -   (e) halo,         -   (f) alkoxy, cyclic alkoxy, or aryloxy,         -   (g) siloxy,         -   (h) alkyleneoxy-alkyl or alkoxy-alkyleneoxy-alkyl, such as             polyethyleneoxyalkyl, polypropyleneoxyalkyl, or             poly(ethyleneoxy-co-propyleneoxyalkyl), or         -   (i) a monovalent siloxane chain comprising from 1 to 100             siloxane repeat units optionally substituted with alkyl,             alkoxy, hydroxy, amino, oxa, carboxy, alkyl carboxy, alkoxy,             amido, carbamate, halo or combinations thereof; and     -   n is from 0 to 500 or from 0 to 200, or from 0 to 100, or from 0         to 20, where it is understood that when n is other than 0, n is         a distribution having a mode equal to a stated value. When n is         2 or more, the SiO units may carry the same or different R^(A)         substituents and if different R^(A) substituents are present,         the n groups may be in random or block configuration.

In Formula A, three R^(A) may each comprise a polymerizable group, alternatively two R^(A) may each comprise a polymerizable group, or alternatively one R^(A) may comprise a polymerizable group.

Examples of silicone-containing components suitable for use in the invention include, but are not limited to, compounds listed in Table 2. Where the compounds in Table 2 contain polysiloxane groups, the number of SiO repeat units in such compounds, unless otherwise indicated, is preferably from 3 to 100, more preferably from 3 to 40, or still more preferably from 3 to 20.

TABLE 2  1 mono-methacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxanes (mPDMS) (preferably containing from 3 to 15 SiO repeating units)  2 mono-acryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxane  3 mono(meth)acryloxypropyl terminated mono-n-methyl terminated polydimethylsiloxane  4 mono(meth)acryloxypropyl terminated mono-n-butyl terminated polydiethylsiloxane  5 mono(meth)acryloxypropyl terminated mono-n-methyl terminated polydiethylsiloxane  6 mono(meth)acrylamidoalkylpolydialkylsiloxanes  7 mono(meth)acryloxyalkyl terminated mono-alkyl polydiarylsiloxanes  8 3-methacryloxypropyltris(trimethylsiloxy)silane (TRIS)  9 3-methacryloxypropylbis(trimethylsiloxy)methylsilane 10 3-methacryloxypropylpentamethyl disiloxane 11 mono(meth)acrylamidoalkylpolydialkylsiloxanes 12 mono(meth)acrylamidoalkyl polydimethylsiloxanes 13 N-(2,3-dihydroxypropane)-N′-(propyl tetra(dimethylsiloxy) dimethylbutylsilane)acrylamide 14 N-[3-tris(trimethylsiloxy)silyl]-propyl acrylamide (TRIS-Am) 15 2-hydroxy-3-[3-methyl-3,3-di(trimethylsiloxy)silylpropoxy]-propyl methacrylate (SiMAA) 16 2-hydroxy-3-methacryloxypropyloxypropyl-tris(trimethylsiloxy)silane 17

mono-(2-hydroxy-3-methacryloxypropyloxy)-propyl terminated mono-n-butyl terminated polydimethylsiloxanes (OH-mPDMS) (containing from 4 to 30, or from 4 to 20, or from 4 to 15 SiO repeat units) 18

19

20

21

22

23

24

Additional non-limiting examples of suitable silicone-containing components are listed in Table 3. Unless otherwise indicated, j2 where applicable is preferably from 1 to 100, more preferably from 3 to 40, or still more preferably from 3 to 15. In compounds containing j 1 and j2, the sum of j1 and j2 is preferably from 2 to 100, more preferably from 3 to 40, or still more preferably from 3 to 15.

TABLE 3 25

26

27

28

29

30 1,3-bis[4-(vinyloxycarbonyloxy)but-1-yl]tetramethyl-disiloxane 31 3-(vinyloxycarbonylthio) propyl-[tris (trimethylsiloxy)silane] 32 3-[tris(trimethylsiloxy)silyl] propyl allyl carbamate 33 3-[tris(trimethylsiloxy)silyl] propyl vinyl carbamate 34 tris(trimethylsiloxy)silylstyrene (Styryl-TRIS) 35

R^(A) = CH₃ (a) or CH₂CH₂CF₃ (b) or CH₂—(CH₂)₂—[OCH₂CH₂]₁₋₁₀—OCH₃ (c); a + b + c = n 36

37

38

39

40

41

Mixtures of silicone-containing components may be used. By way of example, suitable mixtures may include, but are not limited to: a mixture of mono-(2-hydroxy-3-methacryloxypropyloxy)-propyl terminated mono-n-butyl terminated polydimethylsiloxane (OH-mPDMS) having different molecular weights, such as a mixture of OH-mPDMS containing 4 and 15 SiO repeat units; a mixture of OH-mPDMS with different molecular weights (e.g., containing 4 and 15 repeat SiO repeat units) together with a silicone based crosslinker, such as bis-3-acryloxy-2-hydroxypropyloxypropyl polydimethylsiloxane (ac-PDMS); a mixture of 2-hydroxy-3-[3-methyl-3,3-di(trimethylsiloxy)silylpropoxy]-propyl methacrylate (SiMAA) and mono-methacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxane (mPDMS), such as mPDMS 1000.

Silicone-containing components for use in the invention may have an average molecular weight of from about 400 to about 4000 daltons.

The silicone containing component(s) may be present in amounts up to about 95 weight %, or from about 10 to about 80 weight %, or from about 20 to about 70 weight %, based upon all reactive components of the reactive mixture (excluding diluents).

Polyamides

The reactive mixture may include at least one polyamide. As used herein, the term “polyamide” refers to polymers and copolymers comprising repeating units containing amide groups. The polyamide may comprise cyclic amide groups, acyclic amide groups and combinations thereof and may be any polyamide known to those of skill in the art. Acyclic polyamides comprise pendant acyclic amide groups and are capable of association with hydroxyl groups. Cyclic polyamides comprise cyclic amide groups and are capable of association with hydroxyl groups.

Examples of suitable acyclic polyamides include polymers and copolymers comprising repeating units of Formulae G1 and G2:

wherein X is a direct bond, —(CO)—, or —(CONHR₄₄)—, wherein R₄₄ is a C₁ to C₃ alkyl group; R₄₀ is selected from H, straight or branched, substituted or unsubstituted C₁ to C₄ alkyl groups; R₄₁ is selected from H, straight or branched, substituted or unsubstituted C₁ to C₄ alkyl groups, amino groups having up to two carbon atoms, amide groups having up to four carbon atoms, and alkoxy groups having up to two carbon groups; R₄₂ is selected from H, straight or branched, substituted or unsubstituted C₁ to C₄ alkyl groups; or methyl, ethoxy, hydroxyethyl, and hydroxymethyl; R₄₃ is selected from H, straight or branched, substituted or unsubstituted C₁ to C₄ alkyl groups; or methyl, ethoxy, hydroxyethyl, and hydroxymethyl; wherein the number of carbon atoms in R₄₀ and R₄₁ taken together is 8 or less, including 7, 6, 5, 4, 3, or less; and wherein the number of carbon atoms in R₄₂ and R₄₃ taken together is 8 or less, including 7, 6, 5, 4, 3, or less. The number of carbon atoms in R₄₀ and R₄₁ taken together may be 6 or less or 4 or less. The number of carbon atoms in R₄₂ and R₄₃ taken together may be 6 or less. As used herein substituted alkyl groups include alkyl groups substituted with an amine, amide, ether, hydroxyl, carbonyl or carboxy groups or combinations thereof.

R₄₀ and R₄₁ may be independently selected from H, substituted or unsubstituted C₁ to C₂ alkyl groups. X may be a direct bond, and R₄₀ and R₄₁ may be independently selected from H, substituted or unsubstituted C₁ to C₂ alkyl groups. R₄₂ and R₄₃ can be independently selected from H, substituted or unsubstituted C₁ to C₂ alkyl groups, methyl, ethoxy, hydroxyethyl, and hydroxymethyl.

The acyclic polyamides of the present invention may comprise a majority of the repeating units of Formula LV or Formula LVI, or the acyclic polyamides can comprise at least 50 mole percent of the repeating unit of Formula G or Formula G1, including at least 70 mole percent, and at least 80 mole percent. Specific examples of repeating units of Formula G and Formula G1 include repeating units derived from N-vinyl-N-methylacetamide, N-vinylacetamide, N-vinyl-N-methylpropionamide, N-vinyl-N-methyl-2-methylpropionamide, N-vinyl-2-methyl-propionamide, N-vinyl-N,N′-dimethylurea, N, N-dimethylacrylamide, methacrylamide, and acyclic amides of Formulae G2 and G3:

Examples of suitable cyclic amides that can be used to form the cyclic polyamides of include α-lactam, β-lactam, γ-lactam, δ-lactam, and ϵ-lactam. Examples of suitable cyclic polyamides include polymers and copolymers comprising repeating units of Formula G4:

wherein R₄₅ is a hydrogen atom or methyl group; wherein f is a number from 1 to 10; wherein X is a direct bond, —(CO)—, or —(CONHR₄₆)—, wherein R₄₆ is a C₁ to C₃ alkyl group. In Formula LIX, f may be 8 or less, including 7, 6, 5, 4, 3, 2, or 1. In Formula G4, f may be 6 or less, including 5, 4, 3, 2, or 1. In Formula G4, f may be from 2 to 8, including 2, 3, 4, 5, 6, 7, or 8. In Formula LIX, f may be 2 or 3. When X is a direct bond, f may be 2. In such instances, the cyclic polyamide may be polyvinylpyrrolidone (PVP).

The cyclic polyamides of the present invention may comprise 50 mole percent or more of the repeating unit of Formula G4, or the cyclic polyamides can comprise at least 50 mole percent of the repeating unit of Formula G4, including at least 70 mole percent, and at least 80 mole percent.

The polyamides may also be copolymers comprising repeating units of both cyclic and acyclic amides. Additional repeating units may be formed from monomers selected from hydroxyalkyl(meth)acrylates, alkyl(meth)acrylates, other hydrophilic monomers and siloxane substituted (meth)acrylates. Any of the monomers listed as suitable hydrophilic monomers may be used as co-monomers to form the additional repeating units. Specific examples of additional monomers which may be used to form polyamides include 2-hydroxyethyl (meth)acrylate, vinyl acetate, acrylonitrile, hydroxypropyl (meth)acrylate, methyl (meth)acrylate and hydroxybutyl (meth)acrylate, dihydroxypropyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, and the like and mixtures thereof. Ionic monomers may also be included. Examples of ionic monomers include (meth)acrylic acid, N-[(ethenyloxy)carbonyl]-β-alanine (VINAL, CAS #148969-96-4), 3-acrylamidopropanoic acid (ACA1), 5-acrylamidopentanoic acid (ACA2), 3-acrylamido-3-methylbutanoic acid (AMBA), 2-(methacryloyloxy)ethyl trimethylammonium chloride (Q Salt or METAC), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), 1-propanaminium, N-(2-carboxyethyl)-N,N-dimethyl-3-[(1-oxo-2-propen-1-yl)amino]-, inner salt (CBT, carboxybetaine; CAS 79704-35-1), 1-propanaminium, N,N-dimethyl-N-[3-[(1-oxo-2-propen-1-yl)amino]propyl]-3-sulfo-, inner salt (SBT, sulfobetaine, CAS 80293-60-3), 3,5-Dioxa-8-aza-4-phosphaundec-10-en-l-aminium, 4-hydroxy-N,N,N-trimethyl-9-oxo-, inner salt, 4-oxide (9CI) (PBT, phosphobetaine, CAS 163674-35-9, 2-methacryloyloxyethyl phosphorylcholine, 3-(dimethyl(4-vinylbenzyl)ammonio)propane-1-sulfonate (DMVBAPS), 3-((3-acrylamidopropyl)dimethylammonio)propane-1-sulfonate (AMPDAPS), 3-((3-methacrylamidopropyl)dimethylammonio)propane-1-sulfonate (MAMPDAPS), 3-((3-(acryloyloxy)propyl)dimethylammonio)propane-1-sulfonate (APDAPS), methacryloyloxy)propyl)dimethylammonio)propane-1-sulfonate (MAPDAPS).

The reactive monomer mixture may comprise both an acyclic polyamide and a cyclic polyamide or copolymers thereof. The acyclic polyamide can be any of those acyclic polyamides described herein or copolymers thereof, and the cyclic polyamide can be any of those cyclic polyamides described herein or copolymers thereof. The polyamide may be selected from the group polyvinylpyrrolidone (PVP), polyvinylmethyacetamide (PVMA), polydimethylacrylamide (PDMA), polyvinylacetamide (PNVA), poly(hydroxyethyl(meth)acrylamide), polyacrylamide, and copolymers and mixtures thereof. The polyamide may be a mixture of PVP (e.g., PVP K90) and PVMA (e.g., having a M_(w) of about 570 KDa).

The total amount of all polyamides in the reactive mixture may be in the range of between 1 weight percent and about 35 weight percent, including in the range of about 1 weight percent to about 15 weight percent, and in the range of about 5 weight percent to about 15 weight percent, in all cases, based on the total weight of the reactive components of the reactive monomer mixture.

Without intending to be bound by theory, when used with a silicone hydrogel, the polyamide functions as an internal wetting agent. The polyamides of the present invention may be non-polymerizable, and in this case, are incorporated into the silicone hydrogels as semi-interpenetrating networks. The polyamides are entrapped or physically retained within the silicone hydrogels. Alternatively, the polyamides of the present invention may be polymerizable, for example as polyamide macromers or prepolymers, and in this case, are covalently incorporated into the silicone hydrogels. Mixtures of polymerizable and non-polymerizable polyamides may also be used.

When the polyamides are incorporated into the reactive monomer mixture they may have a weight average molecular weight of at least 100,000 daltons; greater than about 150,000; between about 150,000 to about 2,000,000 daltons; between about 300,000 to about 1,800,000 daltons. Higher molecular weight polyamides may be used if they are compatible with the reactive monomer mixture.

Cross-Linking Agents

It is generally desirable to add one or more cross-linking agents, also referred to as cross-linking monomers, multi-functional macromers, and prepolymers, to the reactive mixture. The cross-linking agents may be selected from bifunctional crosslinkers, trifunctional crosslinkers, tetrafunctional crosslinkers, and mixtures thereof, including silicone-containing and non-silicone containing cross-linking agents. Non-silicone-containing cross-linking agents include ethylene glycol dimethacrylate (EGDMA), tetraethylene glycol dimethacrylate (TEGDMA), trimethylolpropane trimethacrylate (TMPTMA), triallyl cyanurate (TAC), glycerol trimethacrylate, methacryloxyethyl vinylcarbonate (HEMAVc), allylmethacrylate, methylene bisacrylamide (MBA), and polyethylene glycol dimethacrylate wherein the polyethylene glycol has a molecular weight up to about 5000 Daltons. The cross-linking agents are used in the usual amounts, e.g., from about 0.000415 to about 0.0156 mole per 100 grams of reactive Formulas in the reactive mixture. Alternatively, if the hydrophilic monomers and/or the silicone-containing components are multifunctional by molecular design or because of impurities, the addition of a cross-linking agent to the reactive mixture is optional. Examples of hydrophilic monomers and macromers which can act as the cross-linking agents and when present do not require the addition of an additional cross-linking agent to the reactive mixture include (meth)acrylate and (meth)acrylamide endcapped polyethers. Other cross-linking agents will be known to one skilled in the art and may be used to make the silicone hydrogel of the present invention.

It may be desirable to select crosslinking agents with similar reactivity to one or more of the other reactive components in the formulation. In some cases, it may be desirable to select a mixture of crosslinking agents with different reactivity in order to control some physical, mechanical or biological property of the resulting silicone hydrogel. The structure and morphology of the silicone hydrogel may also be influenced by the diluent(s) and cure conditions used.

Multifunctional silicone-containing components, including macromers, cross-linking agents, and prepolymers, may also be included to further increase the modulus and retain tensile strength. The silicone containing cross-linking agents may be used alone or in combination with other cross-linking agents. An example of a silicone containing component which can act as a cross-linking agent and, when present, does not require the addition of a crosslinking monomer to the reactive mixture includes a, w-bismethacryloxypropyl polydimethylsiloxane. Another example is bis-3-acryloxy-2-hydroxypropyloxypropyl polydimethylsiloxane (ac-PDMS).

Cross-linking agents that have rigid chemical structures and polymerizable groups that undergo free radical polymerization may also be used. Non-limiting examples of suitable rigid structures include cross-linking agents comprising phenyl and benzyl ring, such are 1,4-phenylene diacrylate, 1,4-phenylene dimethacrylate, 2,2-bis(4-methacryloxyphenyl)-propane, 2,2-bis[4-(2-acryloxyethoxy)phenyl]propane, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)-phenyl]propane, and 4-vinylbenzyl methacrylate, and combinations thereof Rigid crosslinking agents may be included in amounts between about 0.5 and about 15, or 2-10, 3-7 based upon the total weight of all of the reactive components. The physical and mechanical properties of the silicone hydrogels of the present invention may be optimized for a particular use by adjusting the components in the reactive mixture.

Non-limiting examples of silicone cross-linking agents also include the multi-functional silicone-containing components described above, such as compounds of Formula E (and its sub-formulae) and the multi-functional compounds shown in Table 3.

Further Constituents

The reactive mixture may contain additional components such as, but not limited to, diluents, initiators, UV absorbers, visible light absorbers, photochromic compounds, pharmaceuticals, nutraceuticals, antimicrobial substances, tints, pigments, copolymerizable dyes, nonpolymerizable dyes, release agents, and combinations thereof.

Classes of suitable diluents for silicone hydrogel reactive mixtures include alcohols having 2 to 20 carbon atoms, amides having 10 to 20 carbon atoms derived from primary amines and carboxylic acids having 8 to 20 carbon atoms. The diluents may be primary, secondary, and tertiary alcohols.

Generally, the reactive components are mixed in a diluent to form a reactive mixture. Suitable diluents are known in the art. For silicone hydrogels, suitable diluents are disclosed in WO 03/022321 and U.S. Pat. No. 6,020,445, the disclosure of which is incorporated herein by reference. Classes of suitable diluents for silicone hydrogel reactive mixtures include alcohols having 2 to 20 carbons, amides having 10 to 20 carbon atoms derived from primary amines, and carboxylic acids having 8 to 20 carbon atoms. Primary and tertiary alcohols may be used. Preferred classes include alcohols having 5 to 20 carbons and carboxylic acids having 10 to 20 carbon atoms. Specific diluents which may be used include 1-ethoxy-2-propanol, diisopropylaminoethanol, isopropanol, 3,7-dimethyl-3-octanol, 1-decanol, 1-dodecanol, 1-octanol, 1-pentanol, 2-pentanol, 1-hexanol, 2-hexanol, 2-octanol, 3-methyl-3-pentanol, tert-amyl alcohol, tert-butanol, 2-butanol, 1-butanol, 2-methyl-2-pentanol, 2-propanol, 1-propanol, ethanol, 2-ethyl-1-butanol, (3-acetoxy-2-hydroxypropyloxy)-propylbis(trimethylsiloxy) methylsilane, 1-tert-butoxy-2-propanol, 3,3-dimethyl-2-butanol, tert-butoxyethanol, 2-octyl-1-dodecanol, decanoic acid, octanoic acid, dodecanoic acid, 2-(diisopropylamino)ethanol mixtures thereof and the like. Examples of amide diluents include N,N-dimethyl propionamide and dimethyl acetamide.

Preferred diluents include 3,7-dimethyl-3-octanol, 1-dodecanol, 1-decanol, 1-octanol, 1-pentanol, 1-hexanol, 2-hexanol, 2-octanol, 3-methyl-3-pentanol, 2-pentanol, t-amyl alcohol, tert-butanol, 2-butanol, 1-butanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, ethanol, 3,3-dimethyl-2-butanol, 2-octyl-1-dodecanol, decanoic acid, octanoic acid, dodecanoic acid, mixtures thereof and the like.

More preferred diluents include 3,7-dimethyl-3-octanol, 1-dodecanol, 1-decanol, 1-octanol, 1-pentanol, 1-hexanol, 2-hexanol, 2-octanol, 1-dodecanol, 3-methyl-3-pentanol, 1-pentanol, 2-pentanol, t-amyl alcohol, tert-butanol, 2-butanol, 1-butanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, 3,3-dimethyl-2-butanol, 2-octyl-1-dodecanol, mixtures thereof and the like. If a diluent is present, generally there are no particular restrictions with respect to the amount of diluent present. When diluent is used, the diluent may be present in an amount in the range of about 2 to about 70 weight percent, including in the range of about 5 to about 50 weight percent, and in the range of about 15 to about 40 weight percent, based on the total weight of the reactive mixtures (including reactive and nonreactive Formulas). Mixtures of diluents may be used.

A polymerization initiator may be used in the reactive mixture. The polymerization initiator may include, for instance, at least one of lauroyl peroxide, benzoyl peroxide, iso- propyl percarbonate, azobisisobutyronitrile, and the like, that generate free radicals at moderately elevated temperatures, and photoinitiator systems such as aromatic alpha-hydroxy ketones, alkoxyoxybenzoins, acetophenones, acylphosphine oxides, bisacylphosphine oxides, and a tertiary amine plus a diketone, mixtures thereof and the like. Illustrative examples of photoinitiators are 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, bis(2,6-dimethoxybenzoyl)-2,4-4-trimethylpentyl phosphine oxide (DMBAPO), bis(2,4,6-trimethylbenzoyl)-phenyl phosphine oxide (Irgacure 819), 2,4,6-trimethylbenzyldiphenyl phosphine oxide and 2,4,6-trimethylbenzoyl diphenylphosphine oxide, benzoin methyl ester and a combination of cam- phorquinone and ethyl 4-(N,N-dimethylamino)benzoate.

Commercially available (from IGM Resins B.V., The Netherlands) visible light initiator systems include Irgacure® 819, Irgacure® 1700, Irgacure® 1800, Irgacure® 819, Irgacure® 1850 and Lucrin® TPO initiator. Commercially available (from IGM Resins B.V.) UV photoinitiators include Darocur® 1173 and Darocur® 2959. These and other photoinitiators which may be used are disclosed in Volume III, Photoinitiators for Free Radical Cationic & Anionic Photopolymerization, 2nd Edition by J. V. Crivello & K. Dietliker; edited by G. Bradley; John Wiley and Sons; New York; 1998. The initiator is used in the reactive mixture in effective amounts to initiate photopolymerization of the reactive mixture, e.g., from about 0.1 to about 2 parts by weight per 100 parts of reactive monomer mixture. Polymerization of the reactive mixture can be initiated using the appropriate choice of heat or visible or ultraviolet light or other means depending on the polymerization initiator used. Alternatively, initiation can be conducted using e-beam without a photoinitiator. However, when a photoinitiator is used, the preferred initiators are bisacylphosphine oxides, such as bis(2,4,6-tri-methylbenzoyl)-phenyl phosphine oxide (Irgacure® 819) or a combination of 1-hydroxycyclohexyl phenyl ketone and bis(2,6-dimethoxybenzoyl)-2,4-4-trimethylpentyl phosphine oxide (DMBAPO).

The reactive mixture for making the ophthalmic devices of the invention may comprise, in addition to a high energy visible light absorbing compound, any of the polymerizable compounds and optional components described above.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, and a hydrophilic component.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, and a hydrophilic component selected from DMA, NVP, HEMA, VMA, NVA, methacrylic acid, and mixtures thereof. Preferred are mixtures of HEMA and methacrylic acid.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, a hydrophilic component, and a silicone-containing component.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, a hydrophilic component, and a silicone-containing component comprising a compound of formula A.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, a hydrophilic component selected from DMA, NVP, HEMA, VMA, NVA, and mixtures thereof; a silicone-containing component such as a compound of formula A; and an internal wetting agent.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, a hydrophilic component selected from DMA, HEMA and mixtures thereof; a silicone-containing component selected from 2-hydroxy-3-[3-methyl-3,3-di(trimethylsiloxy)silylpropoxy]-propyl methacrylate (SiMAA), mono-methacryloxypropyl terminated mono-n-butyl terminated polydimethylsiloxane (mPDMS), mono-(2-hydroxy-3-methacryloxypropyl)-propyl ether terminated mono-n-butyl terminated polydimethylsiloxane (OH-mPDMS), and mixtures thereof; and a wetting agent (preferably PVP or PVMA). For the hydrophilic component, mixtures of DMA and HEMA are preferred. For the silicone containing component, mixtures of SiMAA and mPDMS are preferred.

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound, a hydrophilic component comprising a mixture of DMA and HEMA; a silicone-containing component comprising a mixture of OH-mPDMS having from 2 to 20 repeat units (preferably a mixture of 4 and 15 repeat units). Preferably, the reactive mixture further comprises a silicone-containing crosslinker, such as ac-PDMS. Also preferably, the reactive mixture contains a wetting agent (preferably DMA, PVP, PVMA or mixtures thereof).

Preferred reactive mixtures may comprise: a high energy visible light absorbing compound, such as a formula I compound; between about 1 and about 15 wt % at least one polyamide (e.g., an acyclic polyamide, a cyclic polyamide, or mixtures thereof); at least one first mono-functional, hydroxyl substituted poly(disubstituted siloxane) having 4 to 8 siloxane repeating units (e.g., OH-mPDMS where n is 4 to 8, preferably n is 4); at least one second hydroxyl substituted poly(disubstituted siloxane) that is a mono-functional hydroxyl substituted poly(disubstituted siloxane)s having 10 to 200 or 10-100 or 10-50 or 10-20 siloxane repeating units (e.g., OH-mPDMS where n is 10 to 200 or 10-100 or 10-50 or 10-20, preferably n is 15); about 5 to about 35 wt % of at least one hydrophilic monomer; and optionally a multifunctional hydroxyl substituted poly(disubstituted siloxane)s having 10 to 200, or 10 to 100 siloxane repeating units (e.g., ac-PDMS). Preferably, the first mono-functional, hydroxyl substituted poly(disubstituted siloxane) and the second hydroxyl substituted poly(disubstituted siloxane) are present in concentrations to provide a ratio of weight percent of the first mono-functional, hydroxyl substituted poly(disubstituted siloxane) to weight percent of the second hydroxyl substituted poly(disubstituted siloxane) of 0.4-1.3, or 0.4-1.0.

The foregoing reactive mixtures may contain optional ingredients such as, but not limited to, one or more initiators, internal wetting agents, crosslinkers, other UV or HEV absorbers, and diluents.

Curing of Hydrogels and Manufacture of Lens

The reactive mixtures may be formed by any of the methods known in the art, such as shaking or stirring, and used to form polymeric articles or devices by known methods. The reactive components are mixed together either with or without a diluent to form the reactive mixture.

For example, ophthalmic devices may be prepared by mixing reactive components, and, optionally, diluent(s), with a polymerization initiator and curing by appropriate conditions to form a product that can be subsequently formed into the appropriate shape by lathing, cutting, and the like. Alternatively, the reactive mixture may be placed in a mold and subsequently cured into the appropriate article.

A method of making a molded ophthalmic device, such as a silicone hydrogel contact lens, may comprise: preparing a reactive monomer mixture; transferring the reactive monomer mixture onto a first mold; placing a second mold on top the first mold filled with the reactive monomer mixture; and curing the reactive monomer mixture by free radical copolymerization to form the silicone hydrogel in the shape of a contact lens.

The reactive mixture may be cured via any known process for molding the reactive mixture in the production of contact lenses, including spincasting and static casting. Spincasting methods are disclosed in U.S. Pat. Nos. 3,408,429 and 3,660,545, and static casting methods are disclosed in U.S. Pat. Nos. 4,113,224 and 4,197,266. The contact lenses of this invention may be formed by the direct molding of the silicone hydrogels, which is economical, and enables precise control over the final shape of the hydrated lens. For this method, the reactive mixture is placed in a mold having the shape of the final desired silicone hydrogel and the reactive mixture is subjected to conditions whereby the monomers polymerize, thereby producing a polymer in the approximate shape of the final desired product.

After curing, the lens may be subjected to extraction to remove unreacted components and release the lens from the lens mold. The extraction may be done using conventional extraction fluids, such organic solvents, such as alcohols or may be extracted using aqueous solutions.

Aqueous solutions are solutions which comprise water. The aqueous solutions of the present invention may comprise at least about 20 weight percent water, or at least about 50 weight percent water, or at least about 70 weight percent water, or at least about 95 weight percent water. Aqueous solutions may also include additional water soluble Formulas such as inorganic salts or release agents, wetting agents, slip agents, pharmaceutical and nutraceutical Formulas, combinations thereof and the like. Release agents are compounds or mixtures of compounds which, when combined with water, decrease the time required to release a contact lens from a mold, as compared to the time required to release such a lens using an aqueous solution that does not comprise the release agent. The aqueous solutions may not require special handling, such as purification, recycling or special disposal procedures.

Extraction may be accomplished, for example, via immersion of the lens in an aqueous solution or exposing the lens to a flow of an aqueous solution. Extraction may also include, for example, one or more of: heating the aqueous solution; stirring the aqueous solution; increasing the level of release aid in the aqueous solution to a level sufficient to cause release of the lens; mechanical or ultrasonic agitation of the lens; and incorporating at least one leaching or extraction aid in the aqueous solution to a level sufficient to facilitate adequate removal of unreacted components from the lens. The foregoing may be conducted in batch or continuous processes, with or without the addition of heat, agitation or both.

Application of physical agitation may be desired to facilitate leach and release. For example, the lens mold part to which a lens is adhered can be vibrated or caused to move back and forth within an aqueous solution. Other methods may include ultrasonic waves through the aqueous solution.

The lenses may be sterilized by known means such as, but not limited to, autoclaving.

The transmission wavelengths and percentages described herein may be measured on various thicknesses of lenses using, for instance, the methodologies described in the Examples. By way of example, a preferred center thickness for measuring transmission spectra in a soft contact lens may be from 80 to 110 microns, or from 90 to 105 microns or from 95 to 105 microns. The measurement may be made at the center of the lens using, for instance, a 4 nm instrument slit width. The concentration of the one or more high energy visible light absorbing compounds may be adjusted to achieve the transmission characteristics described herein. By of example, the concentration may be in the range of at least 0.01 percent, or at least 0.1 percent, or at least 1 percent, or at least 2 percent; and up to 10 percent or up to 5 percent, based on the weight percentages of all components in the reactive mixture, excluding diluent. A typical concentration may be in the range of 1 to 5 percent.

Silicone hydrogel ophthalmic devices (e.g., contact lenses) according to the invention preferably exhibit the following properties. All values are prefaced by “about,” and the devices may have any combination of the listed properties. The properties may be determined by methods known to those skilled in the art, for instance as described in United States pre-grant publication US20180037690, which is incorporated herein by reference.

Water concentration %: at least 20%, or at least 25% and up to 80% or up to 70%

Haze: 30% or less, or 10% or less

Advancing dynamic contact angle (Wilhelmy plate method): 100° or less, or 80° or less; or 50° or less

Tensile Modulus (psi): 150 or less, or 135 or less, 120 or less, or 80 to 135 Oxygen permeability (Dk, barrers): at least 60 barrers, or at least 80, or at least 100, or at least 150, or at least 200

Elongation to Break: at least 100

For ionic silicon hydrogels, the following properties may also be preferred (in addition to those recited above):

Lysozyme uptake (μg/lens): at least 100, or at least 150, or at least 500, or at least 700

Polyquaternium 1 (PQ1) uptake (%): 15 or less, or 10 or less, or 5 or less.

Multifocal contact lenses of the invention may be used to improve one or more vision attributes in a presbyopic contact lens wearer, when compared to a multifocal contact lens that doesn't contain an HEV light absorbing compound. The vision attribute may be overall quality of vision, such as quality of vision indoors and/or outdoors vision. The vision attribute may be clarity of vision, such as clarity of distance vision (looking at things that are more than 5 feet away, such as street signs), clarity of intermediate vision (looking at things 2-3 feet away, such as a computer screen), clarity of near vision (looking at things close up, such as reading a book), clarity of vision at the end of the day, and/or clarity of vision during daily activities. The vision attribute may be glare reduction, such as reduction of glare while driving at night, reduction of glare while driving during the day, reduction of glare caused by bright indoor lights, reduction of glare caused by bright light coming through a window, reduction of glare caused by bright sunlight, and/or reduction of glare caused by a computer screen. The vision attribute may be reduction of squinting, such as reduction of squinting in bright sunlight, and/or reduction of squinting while working on a computer. The vision attribute may be vision comfort. The vision attribute may be logmar visual acuity. The attribute may be ease of handling. The vision attribute may be improved chromatic contrast.

The following clauses list non-limiting embodiments of the disclosure.

1. A method for improving a vision attribute in a presbyopic contact lens wearer, the method comprising: providing the contact lens wearer with a contact lens that is a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible (HEV) light absorbing compound, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.

2. The method of clause 1 wherein the contact lens transmits from 0 percent to 70 percent of light across a wavelength range of 400 to 409 nm.

3. The method of any one of clauses 1 to 2 wherein the contact lens transmits 45 percent or less of light across a wavelength range of 280 to 399 nm.

4. The method of any one of clauses 1 to 3 wherein the contact lens transmits at least 80 percent of light across a wavelength range of 450 to 800 nm.

5. The method of any one of clauses 1 to 4 wherein the contact lens is photostable.

6. The method of any one of clauses 1 to 5 wherein the high energy visible light absorbing compound is a static compound.

7. The method of any one of clauses 1 to 6 wherein the high energy visible light absorbing compound comprises a compound of formula I:

wherein:

-   -   m and n are independently 0, 1, 2, 3, or 4;     -   T is a bond, O, or NR;     -   Y is a linking group;     -   P_(g) is a polymerizable group;     -   R at each occurrence is independently H, C₁-C₆ alkyl,         cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or Y-P_(g); and     -   R¹ and R², when present, are independently at each occurrence         C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ thioalkyl, C₃-C₇ cycloalkyl,         aryl (preferably unsubstituted phenyl or phenyl substituted with         alkyl or halo), halo, hydroxy, amino, NR³R⁴, or benzyl, wherein         R³ and R⁴ are independently H or C₁-C₆ alkyl, or two adjacent R¹         or R² groups, together with the carbon atoms to which they are         attached, combine to form a cycloalkyl or aryl ring. Compounds         of formula I preferably contain one or two Y-P_(g) groups. More         preferably, the compounds contain one Y-P_(g) group.

8. The method of clause 7 wherein m and n are each independently 0 or 1.

9. The method of any one of clauses 7 to 8 wherein Y at each occurrence is independently alkylene, cycloalkylene, heterocycloalkylene, arylene, heteroarylene, oxaalkylene, alkylene-amide-alkylene, alkylene-amine-alkylene, or combinations thereof.

10. The method of any one of clauses 7 to 9 wherein P_(g) comprises styryl, vinyl carbonate, vinyl ether, vinyl carbamate, N-vinyl lactam, N-vinylamide, (meth)acrylate, or (meth)acrylamide.

11. Use of a multifocal contact lens for improving at least one vision attribute selected from quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast, the contact lens being a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible light absorbing compound.

12. The use of clause 11 wherein the contact lens transmits from 0 percent to 70 percent of light across a wavelength range of 400 to 409 nm.

13. The use of any one of clauses 11 to 12 wherein the contact lens transmits 45 percent or less of light across a wavelength range of 280 to 399 nm.

14. The use of any one of clauses 11 to 13 wherein the contact lens transmits at least 80 percent of light across a wavelength range of 450 to 800 nm.

15. The use of any one of clauses 11 to 14 wherein the contact lens is photostable.

16. The use of any one of clauses 11 to 15 wherein the high energy visible light absorbing compound is a static compound.

17. The use of any one of clauses 11 to 16 wherein the high energy visible light absorbing compound comprises a compound of formula I:

wherein:

-   -   m and n are independently 0, 1, 2, 3, or 4;     -   T is a bond, O, or NR;     -   Y is a linking group;     -   P_(g) is a polymerizable group;     -   R at each occurrence is independently H, C₁-C₆ alkyl,         cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or Y-P_(g); and     -   R¹ and R², when present, are independently at each occurrence         C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ thioalkyl, C₃-C₇ cycloalkyl,         aryl (preferably unsubstituted phenyl or phenyl substituted with         alkyl or halo), halo, hydroxy, amino, NR³R⁴, or benzyl, wherein         R³ and R⁴ are independently H or C₁-C₆ alkyl, or two adjacent R¹         or R² groups, together with the carbon atoms to which they are         attached, combine to form a cycloalkyl or aryl ring. Compounds         of formula I preferably contain one or two Y-P_(g) groups. More         preferably, the compounds contain one Y-P_(g) group.

18. The use of clause 17 wherein m and n are each independently 0 or 1.

19. The use of any one of clauses 17 to 18 wherein Y at each occurrence is independently alkylene, cycloalkylene, heterocycloalkylene, arylene, heteroarylene, oxaalkylene, alkylene-amide-alkylene, alkylene-amine-alkylene, or combinations thereof.

20. The use of any one of clauses 17 to 19 wherein P_(g) comprises styryl, vinyl carbonate, vinyl ether, vinyl carbamate, N-vinyl lactam, N-vinylamide, (meth)acrylate, or (meth)acrylamide.

21. An intraocular lens that is a free radical reaction product of a reactive mixture comprising:

-   -   one or more polymerizable compounds suitable for making the         intraocular lens; and     -   a high energy visible (HEV) light absorbing compound,         wherein the intraocular lens is a multifocal intraocular lens.

22. The intraocular lens of clause 21 that transmits from 0 percent to 70 percent of light across a wavelength range of 400 to 409 nm.

23. The intraocular lens of any one of clauses 21 to 22 that transmits 45 percent or less of light across a wavelength range of 280 to 399 nm.

24. The intraocular lens of any one of clauses 21 to 23 that transmits at least 80 percent of light across a wavelength range of 450 to 800 nm.

25. The intraocular lens of any one of clauses 21 to 24 that is photostable.

26. The intraocular lens of any one of clauses 21 to 25 that is a multifocal toric intraocular lens.

27. The intraocular lens of any one of clauses 21 to 26 wherein the high energy visible light absorbing compound is a static compound.

28. The intraocular lens of any one of clauses 21 to 27 wherein the high energy visible light absorbing compound comprises a compound of formula I:

wherein:

-   -   m and n are independently 0, 1, 2, 3, or 4;     -   T is a bond, O, or NR;     -   Y is a linking group;     -   P_(g) is a polymerizable group;     -   R at each occurrence is independently H, C₁-C₆ alkyl,         cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or Y-P_(g); and     -   R¹ and R², when present, are independently at each occurrence         C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ thioalkyl, C₃-C₇ cycloalkyl,         aryl (preferably unsubstituted phenyl or phenyl substituted with         alkyl or halo), halo, hydroxy, amino, NR³R⁴, or benzyl, wherein         R³ and R⁴ are independently H or C₁-C₆ alkyl, or two adjacent R¹         or R² groups, together with the carbon atoms to which they are         attached, combine to form a cycloalkyl or aryl ring.

29. The intraocular lens of clause 28 wherein m and n are each independently 0 or 1.

30. The intraocular lens of any one of clauses 28 to 29 wherein Y at each occurrence is independently alkylene, cycloalkylene, heterocycloalkylene, arylene, heteroarylene, oxaalkylene, alkylene-amide-alkylene, alkylene-amine-alkylene, or combinations thereof.

31. The intraocular lens of any one of clauses 28 to 30 wherein P_(g) comprises styryl, vinyl carbonate, vinyl ether, vinyl carbamate, N-vinyl lactam, N-vinylamide, (meth)acrylate, or (meth)acrylamide.

32. The intraocular lens of any one of clauses 21 to 31 further comprising a UV absorbing compound.

33. The intraocular lens of clause 32 wherein the UV absorbing compound comprises a compound of formula I, a benzophenone, a benzotriazole, a triazine, a substituted acrylonitrile, a salicyclic acid derivative, a benzoic acid derivative, a cinnamic acid derivative, a chalcone derivative, a dypnone derivative, a crotonic acid derivative, or mixtures thereof.

34. The intraocular lens of any one of clauses 21 to 33 wherein the polymerizable compound suitable for making the intraocular lens comprises a hydrophilic component, a silicone-containing component, or mixtures thereof.

35. A method for improving a vision attribute in a presbyopic intraocular lens wearer, the method comprising: providing the presbyopic intraocular lens wearer with an intraocular lens according to any one of clauses 21 to 34, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.

36. Use of a multifocal intraocular lens according to any one of clauses 21 to 34 for improving at least one vision attribute in a presbyopic intraocular lens wearer, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.

37. A method for improving a vision attribute in a presbyopic intraocular lens wearer, the method comprising:

-   -   providing the presbyopic intraocular lens wearer with a         multifocal intraocular lens that is a free radical reaction         product of a reactive mixture comprising:         -   one or more polymerizable compounds suitable for making the             intraocular lens; and         -   a high energy visible (HEV) light absorbing compound,             wherein the vision attribute is selected from one or more of             quality of vision, clarity of vision, glare reduction,             reduction of squinting, and chromatic contrast.

38. Use of a multifocal intraocular lens for improving at least one vision attribute selected from quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast, the multifocal intraocular lens being a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the intraocular lens; and a high energy visible light absorbing compound.

Some embodiments of the invention will now be described in detail in the following Examples.

EXAMPLES Test Methods

Ultraviolet-visible spectra of compounds in solution were measured on a Perkin Elmer Lambda 45 or an Agilent Cary 6000i UV/VIS scanning spectrometer. The instrument was thermally equilibrated for at least thirty minutes prior to use. For the Perkin Elmer instrument, the scan range was 200-800 nm; the scan speed was 960 nm per minute; the slit width was 4 nm; the mode was set on transmission or absorbance; and baseline correction was selected. For the Cary instrument, the scan range was 200-800 nm; the scan speed was 600 nm/min; the slit width was 2 nm; the mode was transmission or absorbance; and baseline correction was selected. A baseline correction was performed before samples were analyzed using the autozero function.

Ultraviolet-visible spectra of contact lenses formed in part from the claimed compositions were measured on a Perkin Elmer Lambda 45 UV/VIS or an Agilent Cary 6000i UV/VIS scanning spectrometer using packing solution. The instrument was thermally equilibrated for at least thirty minutes prior to use. For the Perkin Elmer instrument, the scan range was 200-800 nm; the scan speed was 960 nm per minute; the slit width was 4 nm; the mode was set on transmission; and baseline correction was selected. Baseline correction was performed using cuvettes containing plastic two-piece lens holders and the same solvents. These two-piece contact lens holders were designed to hold the sample in the quartz cuvette in the location through which the incident light beam traverses. The reference cuvette also contained a two-piece holder. To ensure that the thickness of the samples is constant, all lenses were made using identical molds. The center thickness of the contact lens was measured using an electronic thickness gauge. Reported center thickness and percent transmission spectra are obtained by averaging three individual lens data.

It is important to ensure that the outside surfaces of the cuvette are completely clean and dry and that no air bubbles are present in the cuvette. Repeatability of the measurement is improved when the reference cuvette and its lens holder remain constant and when all samples use the same sample cuvette and its lens holder, making sure that both cuvettes are properly inserted into the instrument.

The following abbreviations will be used throughout the Examples and Figures and have the following meanings:

BC: back or base curve plastic mold

FC: front curve plastic mold

DMA: N, N-dimethylacrylamide (Jarchem)

HEMA: 2-hydroxyethyl methacrylate (Bimax)

PVP: poly(N-vinylpyrrolidone) (ISP Ashland)

PDMA: polydimethylacrylamide

PVMA: polyvinylmethyacetamide

EGDMA: ethylene glycol dimethacrylate (Esstech)

TEGDMA: tetraethylene glycol dimethacrylate (Esstech)

Irgacure 819: bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide (BASF or Ciba Specialty Chemicals)

Irgacure 1870: blend of bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphineoxide and 1-hydroxy-cyclohexyl-phenyl-ketone (BASF or Ciba Specialty Chemicals)

mPDMS: mono-n-butyl terminated monomethacryloxypropyl terminated polydimethylsiloxane (Mn=800-1000 daltons) (Gelest)

HO-mPDMS: mono-n-butyl terminated mono-(2-hydroxy-3-methacryloxypropyloxy)-propyl terminated polydimethylsiloxane (Mn=400-1500 daltons) (Ortec or DSM-Polymer Technology Group)

ac-PDMS: bis-3-acryloxy-2-hydroxypropyloxypropyl polydimethylsiloxane (Tegomer V-Si 2250 from Evonik)

Blue HEMA: 1-amino-4-[3-(4-(2-methacryloyloxy-ethoxy)-6-chlorotriazin-2-ylamino)-4-sulfophenylamino]anthraquinone-2-sulfonic acid, as described in U.S. Pat. No. 5,944,853

Da: dalton or g/mole

kDa: kilodalton or an atomic mass unit equal to 1,000 daltons

SiMAA: 2-propenoic acid, 2-methyl-2-hydroxy-3-[3-[1,3,3,3-tetramethyl-1-[(trimethylsilyl)oxy]disiloxanyl]propoxy]propyl ester (Toray) or 3-(3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)propoxy)-2-hydroxypropyl methacrylate

RB247: 1,4-Bis[2-methacryloxyethylamino]-9,10-anthraquinone

BHT:- butylated hydroxytoluene

D30: 3,7-dimethyl-3-octanol (Vigon)

DIW: deionized water

MeOH: methanol

IPA: isopropyl alcohol

HCl: hydrochloric acid

CH₂Cl₂ or DCM: methylene chloride or dichloromethane

SOCl₂: thionyl chloride

mCPBA: m-chloroperbenzoic acid

EtOAc: ethyl acetate

NH₂CH₂CH₂OH: ethanolamine or 2-aminoethanol

Norbloc: 2-(2′-hydroxy-5-methacrylyloxyethylphenyl)-2H-benzotriazole (Janssen)

PP: polypropylene which is the homopolymer of propylene

TT: Tuftec which is a hydrogenated styrene butadiene block copolymer (Asahi Kasei Chemicals)

Z: Zeonor which is a polycycloolefin thermoplastic polymer (Nippon Zeon Co Ltd)

TL03 lights: Phillips TLK 40W/03 bulbs

LED: light emitting diode

¹N NMR: proton nuclear magnetic resonance spectroscopy

UV-VIS: ultraviolet-visible spectroscopy

L: liter

mL: milliliter

Equiv. or eq.: equivalent

kg: kilogram

g: gram

mol: mole

mmol: millimole

min: minute(s)

nm: nanometer(s)

TLC: thin layer chromatography

Borate Buffered Packing Solution: 18.52 grams (300 mmol) of boric acid, 3.7 grams (9.7 mmol) of sodium borate decahydrate, and 28 grams (197 mmol) of sodium sulfate were dissolved in enough deionized water to fill a 2-liter volumetric flask.

Example 1 Synthesis of 2-(2-cyanoacetamido)ethyl methacrylate (A) and 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate (B) as shown in Scheme 2

Methyl cyanoacetate (40 grams, 0.4037 mole) and 25 mL of dichloromethane were stirred in a 3 neck, 500 mL round bottom flask under equipped with a reflux condenser under a nitrogen environment. 2-aminoethanol (23.8 grams, 0.3897 mole, ˜0.97 eq.) was added to the solution via an addition funnel, after which the temperature rose and the methylene chloride began to reflux. After the exotherm ceased, external heat was applied to continue a gentle reflux for a total of two hours, after which no ethanolamine was observed by thin layer chromatography.

The reaction may also be conducted at room temperature and is complete within a few hours.

The mixture was cooled to room temperature and all the methylene chloride was evaporated at reduced pressure. The residual oil was washed three times with 50 mL of ethyl acetate to remove unreacted starting material and non-polar impurities. The residual ethyl acetate was then removed under reduced pressure, and the resulting oil was used for acylation without any further purification.

The crude N-2-hydroxyethylacetamide derivative was dissolved in 150 mL of dichloromethane containing 40 grams of pyridine (˜0.5 mole) in a three-neck round bottom flask equipped with a reflux condenser, an addition funnel, and a magnetic stirring bar. The flask was immersed in an ice bath and allowed to cool down to around 0° C. Methacryloyl chloride (45.76 grams, ˜0.44 mole) was added dropwise from the addition funnel, and the resulting reaction mixture was allowed to warm up to room temperature while constantly stirring the system. Methanol (20 mL) was the added to the flask to quench any unreacted methacryloyl chloride. The volatile components were removed by rotary evaporation under reduced pressure, and the crude product dissolved in 800 mL of dilute aqueous HCl. The resulting aqueous solution was extracted three times with 100 mL of hexanes in a separatory funnel to remove any non-polar impurities. The organic layers were discarded. Sodium chloride was added to the aqueous layer which was then extracted three times with 300 mL of ethyl acetate. About 50 milligrams of BHT were added to the combined organic fractions as an inhibitor, and the ethyl acetate removed by rotary evaporation under reduced pressure. The crude product crystalized out of solution during solvent removal. When about 100 mL of ethyl acetate was left in the flask, 250 mL of hexanes was added, and the crude product was isolated by vacuum filtration using a fritted glass funnel. Thin layer chromatography indicated the presence of a single compound. The filter cake was washed two times with 150 mL of hexanes and then vacuum dried at 40° C., yielding 53 grams (about 70% yield) of 2-(2-cyanoacetamido)ethyl methacrylate (A). ¹H NMR (500 MHz, CDCl₃) δ 1.93 (3H, s, CH₃), 3.36 (2H, s, CNCH₂), 3.60 (2H, dd, CH₂NH), 4.26 (2H, t, CH₂OC═O), 5.59 (1H, m, vinylic), 6.11 (1H, bs, vinylic), 6.52 (1H, bs, NH).

A mixture of 9H-thioxanthene-9-one (2.12 grams, 0.01 mole) and thionyl chloride (5 mL, 8.2 grams, ˜0.07 mole) was refluxed in a 50 mL round bottom flask under a nitrogen atmosphere with constant stirring. After two hours, the red solution was evaporated to dryness ensuring that all unreacted thionyl chloride was removed from the system. 2-(2-Cyanoacetamido)ethyl methacrylate (A) (2.3 grams, 0.0117 mole, ˜1.17 eq.) and 15 mL of dichloromethane were added, and the resulting reaction mixture was heated to reflux under a nitrogen blanket. The reaction was monitored by thin layer chromatography. After two hours, no changes were observed in the chromatogram, so the reactive mixture was allowed to cool down to room temperature. 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate (B) was isolated as yellow crystals (3.2 grams, 82% yield) after passing through a short silica gel column (CH₂Cl₂, followed by 8 weight % EtOAc in CH₂Cl₂). The UV-VIS transmission spectrum of a 0.2 mM methanol solution Compound B is shown in FIG. 1. ¹H NMR (500 MHz, CDCl₃) δ 1.84 (3H, s, CH₃), 3.47 (2H, m, CH₂NH), 4.01 (2H, t, CH₂OC═O), 5.55 (1H, m, vinylic), 5.91 (1H, bs, NH), 5.98 (1H, bs, vinylic), 7.24 (1H, t, Ar-H), 7.31 (1H, t, Ar-H), 7.39 (2H, m, Ar-H), 7.49 (1H, d, Ar-H), 7.55 (1H, m, Ar-H), 7.61 (1H, d, Ar-H), 8.04 (1H, m, Ar-H).

Example 2 Synthesis of 2-(2-cyanoacetamido)ethyl methacrylate (F) and N-(2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl)methacrylamide (G) as shown in Scheme 3

Methyl cyanoacetate (22 grams, 0.22 mole) and 250 mL of dichloromethane were stirred in a 3 neck, 500 mL round bottom flask under equipped with a reflux condenser under a nitrogen environment. The solution is cooled in a water bath and 1,2-diaminoethane (12 grams, 0.2 mole, ˜0.9 eq.) added to the mixture. As the reaction progresses, the mixture appears more and more heterogenous, with the product crashing out of solution. After four hours of stirring at room temperature, the volatiles are evaporated under reduced pressure and the residue is washed with ethyl acetate over a fritted glass funnel and dried at 50° C. prior to further use. ¹H NMR (500 MHz, D₂O) δ 2.74 (2H, t, CH₂NH₂), 3.29 (2H, t, CH₂NH), 3.38 (2H, s, CH₂CN).

2-aminoethyl cyanoacetamide (12.7 g, 0.1 mole) and 12.0 grams of sodium carbonate are stirred in 150 mL of methanol while being chilled in an ice bath. Methacryloyl chloride (11.5 g, 1.1 eq.) is added to the suspension in a dropwise manner, while maintaining the reaction temperature below 30° C. at all times. Once the reaction is complete, evaporate all volatiles under reduced pressure, redissolve the product in acetonitrile and filter the solution to remove all the salts present. Evaporate the acetonitrile under reduced pressure and wash the resulting solids with ethyl acetate over a fritted glass funnel to obtain the desired 2-(2-cyanoacetamido)ethyl methacrylamide (F). ¹H NMR (500 MHz, CD₃OD) δ 1.86 (3H, s, CH₃), 3.22-3.26 (4H, m, NH, CH₂CN), 3.29 (4H, m, CH₂NH), 5.31 (1H, m, vinylic), 5.63 (1H, m, vinylic).

A mixture of thioxanthone (4.24 grams, 0.02 mole) and 8 mL of thionyl chloride (13.12 grams, ˜0.11 mole) was gently refluxed under a nitrogen atmosphere with constant stirring. After two hours of heating, the solution was evaporated to dryness under reduced pressure, ensuring that all unreacted thionyl chloride was removed. 2-(2-cyanoacetamido)ethyl methacrylamide (F) (4.2 grams, ˜1.1 eq.) and 20 mL of degassed methylene chloride were added to the flask, and the mixture was gently refluxed for 3 hours under a nitrogen environment, while monitoring the progress by TLC. The volatiles were evaporated under reduced pressure, and the organics are washed with ethyl acetate. Large quantities of a precipitate enriched with the major product were observed. The suspension was filtered, and the residual solids washed with ethyl acetate prior to drying in a vacuum oven. The UV-VIS transmission spectrum of a 0.2 mM methanolic solution of Compound G is shown in FIG. 2. ¹H NMR (500 MHz, CDCl₃) δ 1.89 (3H, s, CH₃), 3.26 (2H, m, CH₂NH), 3.32 (2H, m, CH₂NH), 5.33 (1H, m, vinylic), 5.68 (1H, m, vinylic), 6.63 (1H, m, NH), 6.49 (1H, m, NH), 7.25 (1H, m, Ar-H), 7.33 (1H, dt, Ar-H), 7.39 (2H, m, Ar-H), 7.51-7.59 (3H, m, Ar-H), 8.05 (1H, m, Ar-H).

Example 3 Synthesis of 2-(2-cyanoacetoxy)ethyl methacrylate (K) and 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetoxy)ethyl methacrylate (L) as shown in Scheme 4

2-(2-Cyanoacetoxy)ethyl methacrylate (K) was prepared by coupling cyanoacetic acid with 2-hydroxyethyl methacrylate as follows. Cyanoacetic acid (9 g, 0.106 mole) and 13 g of 2-hydroxyethyl methacrylate (HEMA, are stirred in 250 mL of dichloromethane, and ethyl dimethylaminopropyl carbodiimide hydrochloride (EDC) is added to the suspension in 4 batches of 5 grams each (20 g, 0.104 mole). The mixture gradually becomes more homogenous as the less polar derivative is formed and volatiles are evaporated under reduced pressure after completion of the reaction. The product is redissolved in a 25:75 mixture of ethyl acetate and hexanes by weight and extracted several times with deionized water to remove any residual salts and unreacted HEMA. A small amount of 4-methoxyhydroquinone (<20 mg) is added to the organic layer and the product is obtained pure after evaporation of the solvents under reduced pressure. ¹H NMR (500 MHz, CDCl₃) δ 1.92 (3H, m, CH₃), 3.47 (2H, S, NCCH₂), 4.36 (2H, m, OCH₂), 4.44 (2H, m, OCH₂), 4.59 (1H, m, vinylic), 6.10 (1H, m, vinylic).

A mixture of thioxanthone (4.24 grams, 0.02 mole) and 8 mL of thionyl chloride (13.12 grams, ˜0.11 mole) was gently refluxed under a nitrogen atmosphere with constant stirring. After two hours of heating, the solution was evaporated to dryness under reduced pressure, ensuring that all unreacted thionyl chloride was removed. A solution of 2-(2-cyanoacetoxy)ethyl methacrylate (K) (4.33 grams, ˜1.1 eq.) in 20 mL of degassed methylene chloride was added to the flask, and the mixture was gently refluxed for 3 hours under a nitrogen environment, while monitoring the progress by TLC. The residue was washed with methanol to remove most of the unreacted starting thioxanthone, re-concentrated, and the crude product was purified by chromatography over a silica gel plug and vacuum dried overnight. The UV-VIS transmission spectrum of a 0.2 mM solution of Compound L in dichloromethane is shown in FIG. 2. ¹H NMR (500 MHz, CDCl₃) δ 1.92 (3H, s, CH₃), 4.36 (2H, m, CH₂), 4.44 (2H, m, CH₂), 5.59 (1H, m, vinylic), 6.10 (1H, m, vinylic), 7.24-7.62 (7H, m, Ar-H), 8.1 (1H, m, Ar-H).

Example 4 Photostability

Non-multifocal silicone hydrogel contact lenses made from a reactive mixture containing compound (B) were subjected to photostability testing as described above. The spectral transmittance results at various wavelengths of the lens containing compound (B) that had been photo-exposed under ICH-Q1B conditions, versus a contact lens containing compound (B) but without photo-exposure are shown Table 4. The data demonstrates that lenses containing HEV light absorbing compounds as described herein are photostable.

TABLE 4 Lens % T % Power exposure Packaging (380-450 nm) Change −3.00 D Control Clear Blister 37 5.4 ICH-Q1B Clear Blister 39 −1.00 D Control Clear Blister 39 0 ICH-Q1B Clear Blister 39 −6.00 D Control Clear Blister 38 0 ICH-Q1B Clear Blister 38

Example 5 Multifocal Silicone Hydrogel Lenses With and Without Compound (B)

Test lenses, which are multifocal silicone hydrogel lenses containing an HEV light absorbing compound (compound (B)) and control lenses (multifocal silicone hydrogel lenses without compound (B)) were prepared composed of 77 weight percent of the formulations listed in Table 5, and 23 weight percent of the diluent D30. The formulations were degassed, dosed into molds, cured and processed into contact lenses. FIG. 1 shows a UV-Vis transmission spectrum of an exemplary multifocal silicone hydrogel lens containing compound (B).

TABLE 5 Weight % Control lens Test lens Component formulation formulation Norbloc 2 1 Irgacure 1870 0.34 0.34 OmniRad 184 0.14 0 (photoinitiator) HEMA 5.85 5.88 DMA 24 23.54 SiMAA2 28 27.36 mPDMS 31 30.56 PVP K-90 7 6.8 TEGDMA 1.65 1.5 Visibility tint 0.02 0.02 Compound (B) 0 3

Example 6 Clinical Testing

Test and control lenses were prepared substantially as described in Example 5. The lenses were subjected to clinical testing in a single-masked, crossover, randomized, dispensing clinical trial. A total of approximately 30 eligible subjects were targeted to complete the study. The subjects were asked to rate various vision attributes of the lenses using a patient reported outcome (PRO) questionnaire. The results are shown in FIG. 2. The left bar in each question is for the control lens, and right bar is for the test lens.

The results demonstrate that lenses of the invention (the test lenses) were preferred over control lenses for a number of vision attributes. Significant differences were observed for overall quality of vision, overall quality of vision indoors and outdoors, clarity of distance vision, clarity of vision at the end of the day, clarity of vision during daily activities, reduction of glare while driving at night, reduction of glare caused by bright indoor lights, and reduction of glare from a computer screen. 

1. A contact lens that is a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible (HEV) light absorbing compound, wherein the contact lens is a multifocal contact lens.
 2. The contact lens of claim 1 that transmits from 0 percent to 70 percent of light across a wavelength range of 400 to 409 nm.
 3. The contact lens of claim 1 that transmits 45 percent or less of light across a wavelength range of 280 to 399 nm.
 4. The contact lens of claim 1 that transmits at least 80 percent of light across a wavelength range of 450 to 800 nm.
 5. The contact lens of claim 1 that is photostable.
 6. The contact lens of claim 1 that is a multifocal toric contact lens.
 7. The contact lens of claim 1 wherein the high energy visible light absorbing compound is a static compound.
 8. The contact lens of claim 1 wherein the high energy visible light absorbing compound comprises a compound of formula I:

wherein: m and n are independently 0, 1, 2, 3, or 4; T is a bond, O, or NR; Y is a linking group; P_(g) is a polymerizable group; R at each occurrence is independently H, C₁-C₆ alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or Y-P_(g); and R¹ and R², when present, are independently at each occurrence C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ thioalkyl, C₃-C₇ cycloalkyl, aryl (preferably unsubstituted phenyl or phenyl substituted with alkyl or halo), halo, hydroxy, amino, NR³R⁴, or benzyl, wherein R³ and R⁴ are independently H or C₁-C₆ alkyl, or two adjacent R¹ or R² groups, together with the carbon atoms to which they are attached, combine to form a cycloalkyl or aryl ring.
 9. The contact lens of claim 8 wherein m and n are each independently 0 or
 1. 10. The contact lens of claim 8 wherein Y at each occurrence is independently alkylene, cycloalkylene, heterocycloalkylene, arylene, heteroarylene, oxaalkylene, alkylene-amide-alkylene, alkylene-amine-alkylene, or combinations thereof.
 11. The contact lens of claim 8 wherein P_(g) comprises styryl, vinyl carbonate, vinyl ether, vinyl carbamate, N-vinyl lactam, N-vinylamide, (meth)acrylate, or (meth)acrylamide.
 12. The contact lens of claim 1 further comprising a UV absorbing compound.
 13. The contact lens of claim 12 wherein the UV absorbing compound comprises a compound of formula I, a benzophenone, a benzotriazole, a triazine, a substituted acrylonitrile, a salicyclic acid derivative, a benzoic acid derivative, a cinnamic acid derivative, a chalcone derivative, a dypnone derivative, a crotonic acid derivative, or mixtures thereof.
 14. The contact lens of claim 1 wherein the polymerizable compound suitable for making the contact lens comprises a hydrophilic component, a silicone-containing component, or mixtures thereof.
 15. A method for improving a vision attribute in a presbyopic contact lens wearer, the method comprising: providing the presbyopic contact lens wearer with a contact lens according to claim 1, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.
 16. Use of a multifocal contact lens according to claim 1 for improving at least one vision attribute in a presbyopic contact lens wearer, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.
 17. A method for improving a vision attribute in a presbyopic contact lens wearer, the method comprising: providing the presbyopic contact lens wearer with a multifocal contact lens that is a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible (HEV) light absorbing compound, wherein the vision attribute is selected from one or more of quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast.
 18. Use of a multifocal contact lens for improving at least one vision attribute selected from quality of vision, clarity of vision, glare reduction, reduction of squinting, and chromatic contrast, the multifocal contact lens being a free radical reaction product of a reactive mixture comprising: one or more polymerizable compounds suitable for making the contact lens; and a high energy visible light absorbing compound.
 19. The method of claim 15 wherein improving a vision attribute comprises an improvement in the vision attribute as observed by a presbyopic contact lens wearer when compared to a multifocal contact lens that does not contain a HEV light absorbing compound.
 20. The contact lens of claim 1 that is imported into a country.
 21. The contact lens of claim 20 wherein the country is the United States of America.
 22. The contact lens of claim 1, wherein the HEV light absorbing compound comprises: 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate; 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl acrylate; N-(2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl)methacrylamide; N-(2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl)acrylamide; 2-(2-cyano-N-methyl-2-(9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate; 2-cyano-2-(9H-thioxanthen-9-ylidene)-N-(2-(N-vinylacetamido)ethyl)acetamide; 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetamido)-2-methylpropyl methacrylate; (E)-2-(2-cyano-2-(2,4-dichloro-9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate; (E)-2-(2-(2-chloro-9H-thioxanthen-9-ylidene)-2-cyanoacetamido)ethyl methacrylate; (E)-2-(2-cyano-2-(2-isopropyl-9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate; (E)-2-(2-cyano-2-(4-isopropyl-9H-thioxanthen-9-ylidene)acetamido)ethyl methacrylate; 2-(2-cyano-2-(9H-thioxanthen-9-ylidene)acetoxy)ethyl methacrylate; or mixtures thereof. 